2023/01/18 更新

写真a

シユエ シヤンウ
薛 献宇
XUE Xianyu
所属
惑星物質研究所 教授
職名
教授
外部リンク

学位

  • 博士(地質学) ( スタンフォード大学 )

研究キーワード

  • 鉱物学・マグマ学・NMR分光学

  • Magmalogy

  • NMR spectroscopy

  • Mineralogy

研究分野

  • 自然科学一般 / 固体地球科学

学歴

  • スタンフォード大学   地球科学研究科  

    - 1993年

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    国名: アメリカ合衆国

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  • Stanford University   School of Earth Sciences   Department of Geology

    - 1993年

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  • 北京大学   地質系  

    - 1984年

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    国名: 中華人民共和国

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  • Peking University   Department of Geology  

    - 1984年

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経歴

  • 岡山大学   惑星物質研究所   所長

    2018年4月 - 2022年3月

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  • 岡山大学   惑星物質研究所   教授

    2016年4月 - 現在

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  • 岡山大学   地球物質科学研究センター   教授

    2015年3月 - 2016年3月

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  • Associate Professor,Institute for Study of the Earth's Interior,Okayama University

    2005年 - 2015年

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  • 岡山大学地球物質科学研究センター 准教授

    2005年 - 2015年

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所属学協会

委員歴

  • 日本鉱物科学会   会員  

    2007年   

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    団体区分:学協会

    日本鉱物科学会

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論文

  • Experimental evidence of static disorder of carbonate ions in Ba-doped calcite

    Shiho Marugata, Hiroyuki Kagi, Yuta Ijichi, Kazuki Komatsu, Xianyu Xue, Kazumasa Sugiyama

    JOURNAL OF SOLID STATE CHEMISTRY   312   2022年8月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ACADEMIC PRESS INC ELSEVIER SCIENCE  

    Incorporation of structurally incompatible Ba2+ into calcite by crystallization via amorphous calcium carbonate induces extinction of 113 reflection in X-ray diffraction patterns even at room temperature. Recently, this phenomenon has been hypothesized as deriving from the static disorder of CO32- in Ba-doped calcite, creating a marked increase in the unit-cell volume. To clarify this hypothesis by experiments, behaviors of CO32- and local structures in Ba-doped calcite samples were investigated. Powder X-ray diffraction (XRD) and differential scanning calorimetry (DSC) indicate that CO32- ions in Ba-doped calcite are disordered, even at 91K. C-13 MAS NMR spectra suggest that Ba atoms in calcite are substituted randomly for Ca atoms. The Ca K-edge X-ray absorption fine structure (XAFS) and the IR absorption spectra indicated reduction of CO32- symmetry with increasing Ba content. These local structure changes by incorporation of incompatible Ba2+ into calcite cause static disorder of CO32- at room temperature.

    DOI: 10.1016/j.jssc.2022.123258

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  • Comment on "Towards the reconciliation of viscosity change and CO2-induced polymerization in silicate melts" by Yann Morizeta, Michael Paris, David Sifre, Ida Di Carlo, Sandra Ory, and Fabrice Gaillard [Chemical Geology 458 (2017) 38-47]

    Xianyu Xue

    CHEMICAL GEOLOGY   550   2020年9月

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    記述言語:英語   出版者・発行元:ELSEVIER  

    The recent paper by Morizet et al. (2017) has presented new O-17 and Si-29 MAS NMR data on CO2-bearing depolymerized aluminosilicate glasses to shed light on the effect of CO2 dissolution on the structure and properties of silicate melts. These data gave convincing new evidence for the dissolution of CO2 in silicate melts/ glasses as free carbonate species, i.e. carbonate ions that are only bonded to network modifiers (e.g. Na, Ca, Mg), but not to the network formers (Si, Al), as well as direct evidence for the accompanying polymerization on the network structure. Together with glass transition temperature measurement, the study provided new insight into the effect of CO2 on the viscosity of depolymerized silicate melts.Here I would like to point out a few errors in the paper, e.g. in the estimation method for the parameter related to the degree of depolymerization from O-17 NMR data, in its expected correlation with CO2 content, which led to an apparent observation that change in degree of polymerization is more than explainable by the formation of free carbonate species. The authors attempted to explain the latter by the change of Si Qn speciation derived from Si-29 MAS NMR data, although these data are actually consistent with the formation of free carbonate species. Once the errors are corrected, their data can be shown to be quantitatively in agreement with the expected change of melt polymerization accompanying the formation of free carbonate species. It is hoped that the clarification of these errors here will reinforce the scientific value of the original, landmark work.

    DOI: 10.1016/j.chemgeo.2020.119675

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  • Carbonate speciation in depolymerized and polymerized (alumino) silicate glasses: Constraints from C-13 MAS and static NMR measurements and ab initio calculations

    Xianyu Xue, Masami Kanzaki, Paul Floury, Tsubasa Tobase, James Eguchi

    CHEMICAL GEOLOGY   479   151 - 165   2018年2月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ELSEVIER SCIENCE BV  

    Knowledge of the dissolution mechanisms of carbon dioxide in silicate melts/glasses is indispensable for understanding its effects on physical and thermodynamic properties. Carbon dioxide is generally known to dissolve as molecular CO2 and CO32- species, with the latter dominant for depolymerized compositions. However, less is agreed upon about how the CO32- groups are incorporated, especially for depolymerized silicate melt compositions relevant to natural mafic and ultramafic magmas. Here we report C-13 MAS and static NMR results on a series of (CO2)-C-13-bearing glasses (quenched from melts) of diverse silicate compositions, including nominally fully polymerized sodium aluminosilicate and calcium aluminosilicate, depolymerized sodium silicate and sodium aluminosilicate, and depolymerized calcium-magnesium silicate and calcium aluminosilicate compositions (with varying degrees of polymerization), as well as ab initio calculations, to provide new constraints on the speciation of carbonates in silicate melts/glasses as a function of composition.The ab initio calculation revealed that both vibrational frequencies and C-13 chemical shift tensor are sensitive to the local environments of carbonates. The splittings of the asymmetric stretching doublets (Delta v(3)) for CO32- groups bonded to one or two tetrahedral Si/Al via two oxygens (network carbonates) are all relatively large (around 180-480 cm(-1)), contrary to previous speculations. In comparison, experimental data for CO(3)(2-)groups bonded only to metal cations (free carbonates) in minerals show zero to moderate Delta v(3) (up to similar to 100 cm(-1)). Our calculations also showed that network carbonates bonded to one or two tetrahedral Si/Al both show C-13 chemical shift tensor parameters (especially skew and isotropic chemical shift) that are distinctly different from those of free carbonates.Our C-13 MAS and static NMR data, as well as infrared spectroscopic data (moderate Delta v(3) of 60-100 cm(-1)) from the literature, for depolymerized silicate and aluminosilicate glasses are all indicative of free carbonates as the dominant species. Data for nominally fully polymerized aluminosilicate compositions, on the other hand, are consistent with carbonate groups bonded to two Si/Al via two oxygens (network carbonate) as the dominant species. The quantitative C-13 MAS NMR data also revealed the coexistence of a small amount of the other type of carbonate species, especially for Ca aluminosilicate glasses. These new structural insights should be valuable in helping better understand physical properties (e.g. viscosity) of CO2-bearing silicate melts of diverse compositions.

    DOI: 10.1016/j.chemgeo.2018.01.005

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  • Protoenstatite in MgSiO3 samples prepared by conventional solid state reaction

    Masami Kanzaki, Xianyu Xue

    JOURNAL OF MINERALOGICAL AND PETROLOGICAL SCIENCES   112 ( 6 )   359 - 364   2017年12月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:JAPAN ASSOC MINERALOGICAL SCIENCES  

    Enstatite (MgSiO3) sample was prepared by conventional solid state reaction at 1500 degrees C, followed by cooling to ambient temperature with different cooling rates (0.04-500 degrees C/s). Quantitative analysis of enstatite phases in the samples by Rietveld refinement and Si-29 MAS NMR revealed that a large amount of metastable protoenstatite (30-40 mol%) along with clinoenstatite was preserved in all samples. The presence of protoenstatite was also confirmed by micro-Raman spectroscopy. The crystal structures of protoenstatite and clinoenstatite at room temperature were refined using the Rietveld method, and were essentially the same as those reported by previous studies. As the solid state reaction method is commonly used to prepare synthetic clinoenstatite, the present result implies that the 'clinoenstatite' starting materials used in previous phase equilibrium studies of MgSiO3 pyroxene might contain overlooked protoenstatite, which could affect the interpretation for phase transition and thus those results should be reexamined.

    DOI: 10.2465/jmps.170616

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  • Crystal structures of two oxygen-deficient perovskite phases in the CaSiO3-CaAlO2.5 join

    Masami Kanzaki, Xianyu Xue, Ye Wu, Shufang Nie

    PHYSICS AND CHEMISTRY OF MINERALS   44 ( 10 )   717 - 733   2017年11月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:SPRINGER  

    The crystal structures of Ca(Al0.5Si0.5)O-2.75 and Ca(Al0.4Si0.6)O-2.8 ordered oxygen-deficient perovskite phases are synthesized at 7 and 11 GPa, respectively, and 1500 A degrees C, and were studied using NMR and synchrotron powder X-ray diffraction. Si-29 MAS NMR, Al-27 MAS and 3Q MAS NMR measurements revealed a single tetrahedral Si and single octahedral Al peak for the Ca(Al0.5Si0.5)O-2.75 phase, and a tetrahedral and an octahedral Si peak and a single octahedral Al peak for the Ca(Al0.4Si0.6)O-2.8 phase. Using this structural information as constraints, the crystal structures were solved from synchrotron X-ray diffraction data by the structure determination from powder diffraction (SDPD) technique. To double-check the structures, first-principles calculations of NMR parameters (chemical shifts and electric field gradients) were also conducted after relaxing the obtained structures. The calculated NMR parameters of both phases are consistent with the observed NMR spectra. The crystal structures of both phases consist of a perovskite-like layer of (Al,Si)O-6 octahedra and a double-layer of SiO4 tetrahedra that are stacked alternatively in the [111] direction of ideal cubic perovskite. The perovskite-like layer is made of a double-layer of Al octahedra for the Ca(Al0.5Si0.5)O-2.75 phase, and a triple-layer with a Si octahedral layer sandwiched between two Al octahedral layers for the Ca(Al0.4Si0.6)O-2.8 phase. A unique feature common to both structures is that each SiO4 tetrahedron has one terminal oxygen that is not shared by other Si or Al. Homologous relation among these phases and merwinite (Ca3MgSi2O8) in terms of different numbers (1-3) of octahedral layers within the perovskite-like layer is noted.

    DOI: 10.1007/s00269-017-0896-z

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  • Hydrogen incorporation mechanisms in forsterite: New insights from H-1 and Si-29 NMR spectroscopy and first-principles calculation

    Xianyu Xue, Masami Kanzaki, Doreen Turner, Dominik Loroch

    AMERICAN MINERALOGIST   102 ( 3 )   519 - 536   2017年3月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:MINERALOGICAL SOC AMER  

    The presence of water (hydrogen) in nominally anhydrous mantle minerals may have profound effects on their physical properties (e.g., electrical conductivity, diffusivity, rheology), and these effects are expected to depend on how water is incorporated in the crystal structure. For olivine, the most abundant upper mantle mineral, despite extensive studies, mostly using vibrational spectroscopy, the interpretations are still not well constrained. To provide better understanding on this issue, we carried out a comprehensive H-1 and Si-29 NMR study on an Mg2SiO4 forsterite sample containing about 0.5 wt% H2O synthesized at 12 GPa and 1200 degrees C, complemented by Raman measurement and first-principles calculation of the geometry, stability, and NMR parameters of model structures. The Raman spectra contain relatively sharp O-H stretching bands near 3612, 3579, and 3567 cm(-1) and a broader band near 3547 cm(-1), similar to previous reports. The H-1 static and MAS NMR data revealed that there are two main populations of protons in the hydrous forsterite structure, one experiencing strong (H-1H)-H-1 homonuclear dipolar couplings and contributing to a broad peak near 2.4 ppm, and another with weaker dipolar couplings and contributing to a narrower peak near 1.2 ppm in the MAS NMR spectrum at 30 kHz. Two-dimensional H-1 CRAMPS-MAS NMR measurements confirmed that the two proton components belong to the same phase and the contrast in MAS NMR peak width is largely due to difference in the strength of H-1-H-1 homonuclear dipolar couplings. In addition, there is also a very weak, narrow H-1 MAS NMR peak near 7.3 ppm (contributing to < 0.1% of the total intensity) due to protons that are more remote from the two main components. First-principles calculation confirmed that the two main proton components can be attributed to the hydrogarnet-like substitution mechanism of four H ions for one Si [(4H) Si] in a tetrahedral site of olivine, but unlike hydrogarnet with one of the protons pointing away from the tetrahedral center and located in an adjacent interstitial site, thus experiencing weaker dipolar couplings than those in the vicinity of the vacant tetrahedron; the very weak narrow peak near 7.3 ppm can be attributed to the substitution mechanism of two H ions for one Mg in an M1 site [(2H)M-1] of forsterite. The H-1-Si-29 CP-MAS NMR spectra revealed both a broad peak encompassing the position for OH defect-free forsterite (-61.7 ppm) and a narrower peak at higher frequency (-60.9 ppm). First-principles calculation indicates that these peaks are accountable by the same models as for the H-1 NMR data. Thus, this study has provided unambiguous evidence supporting that hydrogen is incorporated in forsterite at relatively high-pressure dominantly as (4H) Si defects, with (2H) M1 defects playing only a very minor role. The much larger H-1 chemical shift for protons associated with the latter (than the former) is correlated with stronger hydrogen bonding for the latter, which in turn reflects difference in bonding environments of the OH groups (with the latter bonded to a Si, and the former only bonded to Mg). Similar correlation applies to the O-H stretching frequency.The (4H) Si defects are responsible for the observed high-frequency O-H stretching bands (> 3450 cm(-1)), and the (2H) M1 defects give lower frequencies (undetected here due to low abundance, but most likely near 3160-3220 cm(-1) as previously reported) in vibrational spectra. These results can serve as a guide for (re-) interpretation of infrared and Raman spectroscopic data on hydrous olivine produced under different pressure and silica activity conditions, and require reconsideration of any models for the effects of water on physical properties of olivine based on different interpretations of such data. This study also demonstrated the usefulness of the combined solid-state NMR and first-principles calculation approach in unraveling the hydrogen incorporation mechanisms in nominally anhydrous minerals.

    DOI: 10.2138/am-2017-5878

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  • Cation distribution in Mg-Zn olivine solid solution: a Si-29 MAS NMR and first-principles calculation study

    Masami Kanzaki, Xianyu Xue

    JOURNAL OF MINERALOGICAL AND PETROLOGICAL SCIENCES   111 ( 4 )   292 - 296   2016年8月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:JAPAN ASSOC MINERALOGICAL SCIENCES  

    In order to clarify cation distributions in the M1 and M2 sites of (Mg,Zn)(2)SiO4 olivine solid solution, Si-29 MAS NMR spectroscopic measurement and first-principles NMR parameter calculation were conducted. The Si-29 MAS NMR spectra of (Mg0.95Zn0.05)(2)SiO4 and (Mg0.90Zn0.10)(2)SiO4 olivine samples reveled three new peaks at relative chemical shift differences of 0.2, 1.1 and 2.3 ppm from the main peak of forsterite (-61.8 ppm). These shifts can be attributed to changes in the second-nearest-neighbors of Si due to substitution of Mg by Zn. Based on first-principles calculations, these peaks can be assigned to the following three groups of local Si environments in the order of increasing shift from the main peak of forsterite: i) Si tetrahedra with one corner-shared Zn in M1 or M2 octahedron, ii) Si tetrahedra with one edge-shared Zn in M2 octahedron, and iii) Si tetrahedra with one edge-shared Zn in M1 octahedron. Since the last two peaks are well separated from the others, the relative abundances of Zn in the M1 and M2 sites can be quantified using these peaks. Preference of Zn for M1 site over M2 site was inferred from the observed peak intensities. The present study demonstrated the usefulness of 29Si MAS NMR spectroscopy for quantitatively studying cation distributions in solid solutions.

    DOI: 10.2465/jmps.151104a

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  • Hydroxyl speciation in felsic magmas

    Wim J. Malfait, Xianyu Xue

    GEOCHIMICA ET COSMOCHIMICA ACTA   140   606 - 620   2014年9月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:PERGAMON-ELSEVIER SCIENCE LTD  

    The hydroxyl speciation of hydrous, metaluminous potassium and calcium aluminosilicate glasses was investigated by Al-27-H-1 cross polarization and quantitative H-1 MAS NMR spectroscopy. Al-OH is present in both the potassium and the calcium aluminosilicate glasses and its H-1 NMR partial spectrum was derived from the Al-27-H-1 cross polarization data. For the calcium aluminosilicate glasses, the abundance of Al-OH could not be determined because of the low spectral resolution. For the potassium aluminosilicate glasses, the fraction of Al-OH was quantified by fitting its partial spectrum to the quantitative H-1 NMR spectra. The degree of aluminum avoidance and the relative tendency for Si-O-Si, Si-O-Al and Al-O-Al bonds to hydrolyze were derived from the measured species abundances. Compared to the sodium, lithium and calcium systems, potassium aluminosilicate glasses display a much stronger degree of aluminum avoidance and a stronger tendency for the Al-O-Al linkages to hydrolyze. Combining our results with those for sodium aluminosilicate glasses (Malfait and Xue, 2010a), we predict that the hydroxyl groups in rhyolitic and phonolitic magmas are predominantly present as Si-OH (84-89% and 68-78%, respectively), but with a significant fraction of Al-OH (11-16% and 22-32%, respectively). For both rhyolitic and phonolitic melts, the AlOH/(AlOH + SiOH) ratio is likely smaller than the Al/(Al + Si) ratio for the lower end of the natural temperature range but may approach the Al/(Al + Si) ratio at higher temperatures. (C) 2014 Elsevier Ltd. All rights reserved.

    DOI: 10.1016/j.gca.2014.05.017

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  • NMR Spectroscopy of Inorganic Earth Materials

    Jonathan F. Stebbins, Xianyu Xue

    SPECTROSCOPIC METHODS IN MINERALOLOGY AND MATERIALS SCIENCES   78   605 - 653   2014年

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    記述言語:英語   掲載種別:論文集(書籍)内論文   出版者・発行元:MINERALOGICAL SOC AMER & GEOCHEMICAL SOC  

    DOI: 10.2138/rmg.2014.78.15

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  • Crystal structures of Zn2SiO4 III and IV synthesized at 6.5-8 GPa and 1,273 K

    Xianyu Liu, Masami Kanzaki, Xianyu Xue

    PHYSICS AND CHEMISTRY OF MINERALS   40 ( 6 )   467 - 478   2013年6月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:SPRINGER  

    We report the crystal structures determined under ambient condition for two Zn2SiO4 polymorphs synthesized at 6.5 GPa and 1,273 K (phase III) and 8 GPa and 1,273 K (phase IV) and also compare their Si-29 MAS NMR spectroscopic characteristics with those of other Zn2SiO4 polymorphs (phases I, II and V). Electron microprobe analysis revealed that both of phases III and IV are stoichiometric like the lower-pressure polymorphs (phases I and II), contrary to previous report. The crystal structures were solved using an ab initio structure determination technique from synchrotron powder X-ray diffraction data utilizing local structural information from Si-29 MAS NMR as constraints and were further refined with the Rietveld technique. Phase III is orthorhombic (Pnma) with a = 10.2897(5), b = 6.6711(3), c = 5.0691(2) a"<<. It is isostructural with the high-temperature (Zn1.1Li0.6Si0.3)SiO4 phase and may be regarded as a 'tetrahedral olivine' type that resembles the 'octahedral olivine' structure in the (approximately hexagonally close packed) oxygen arrangement and tetrahedral Si positions, but has Zn in tetrahedral, rather than octahedral coordination. Phase IV is orthorhombic (Pbca) with a = 10.9179(4), b = 9.6728(4), c = 6.1184(2) a"<<. It also consists of tetrahedrally coordinated Zn and Si and features unique edge-shared Zn2O6 dimers. The volumes per formula under ambient condition for phases III and IV are both somewhat larger than that of the lower-pressure polymorph, phase II, suggesting that the two phases may have undergone structural changes during temperature quench and/or pressure release.

    DOI: 10.1007/s00269-013-0584-6

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  • Structural Characterization of Moganite-Type AlPO4 by NMR and Powder X-ray Diffraction

    Masami Kanzaki, Xianyu Xue

    INORGANIC CHEMISTRY   51 ( 11 )   6164 - 6172   2012年6月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:AMER CHEMICAL SOC  

    Structural characterization of a new high-pressure AlPO4 phase synthesized at 5 GPa and 1500 degrees C is reported. The phase is monoclinic (P2/a) with a = 8.7437(1) angstrom, b = 4.8584(1) angstrom, c = 10.8600(2) angstrom, beta = 90.124(1)degrees (Z = 6). P-31 MAS NMR and two-dimensional (2D) Al-27 triple-quantum (3Q) MAS NMR revealed that it contains two tetrahedral P sites of 1:2 abundance ratio, and two tetrahedral Al sites with 1:2 ratio. 2D P-31 dipolar-recoupled double-quantum (DQ) MAS NMR and Al-27 -> P-31 dipolar-based (through-space) and J coupling-based (through-bond) 3Q-heteronuclear correlation (HETCOR) experiments provided direct information on the linkages of these sites. The crystal structure was solved and refined from synchrotron powder X-ray diffraction data utilizing the information from NMR. The phase is isostructural to moganite, a rare SiO2 polymorph, and its structure can be derived from the latter via an ordered replacement of tetrahedral Si sites by Al and P. The NMR parameters of the phase were also calculated by first-principles method, which are consistent with those observed. Contrary to the other moganite phases known to date (i.e., SiO2 and PON), moganite-AlPO4 has a higher-pressure stability field than the corresponding quartz phase. This is the first moganite-type phase found in the ABX(4) system.

    DOI: 10.1021/ic300167k

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  • Distinct Si-29 MAS NMR Peaks from Si-Al Permutation on Neighboring T Sites of Unequal Si-O-T Angles: Direct Evidence from J-Resolved Experiment on K-Cymrite (KAlSi3O8 center dot H2O)

    Xianyu Xue, Masami Kanzaki

    JOURNAL OF PHYSICAL CHEMISTRY C   116 ( 19 )   10714 - 10722   2012年5月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:AMER CHEMICAL SOC  

    Si-29 MAS NMR is a well-established tool for quantitative characterization of Si-Al distribution in aluminosilicates. In framework aluminosilicates, all tetrahedrally coordinated Si/Al (T) are linked via bridging oxygens to four other Si/Al (Q(4)). Each crystallographically unique T site is commonly assumed to give at most five Si-29 NMR peaks with chemical shift spacing around 5 ppm, corresponding to five Si units each linked to nSi and (4 - n)Al (n = 0-4), abbreviated as Si(nSi) hereafter. Here we report a detailed one- and two-dimensional (2D) Si-29 NMR study on K-cymrite (KAlSi3O8 center dot H2O), which possesses a double-layered structure with all Si/Al distributed in one crystallographically unique T site (Q(4)). Contrary to general belief, more than five Si-29 MAS NMR peaks were resolved. These peaks are attributable, via 2D J-coupling mediated experiments, to Si(nSi)(n = 0-4), with two peaks each (similar to 2 ppm spacing) for n = 1-3. The latter corresponds to different permutations of the nSi(4 - n)Al over neighboring T sites of two distinct Si-O-T angles (139 and 180 degrees). This suggests for the first time that the Si-29 chemical shift varies with Si-O-Si and Si-O-Al angles differently. Si-Al exchange over neighboring T sites of unequal Si-O-T angles is another possible cause for multiple Si-29 NMR peaks.

    DOI: 10.1021/jp3008859

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  • Raman and NMR spectroscopic characterization of high-pressure K-cymrite (KAlSi3O8 center dot H2O) and its anhydrous form (kokchetavite)

    Masami Kanzaki, Xianyu Xue, Julien Amalberti, Qian Zhang

    JOURNAL OF MINERALOGICAL AND PETROLOGICAL SCIENCES   107 ( 2 )   114 - 119   2012年4月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:JAPAN ASSOC MINERALOGICAL SCIENCES  

    To facilitate identification of high-pressure K-cymrite (KAlSi3O8 center dot H2O) phase and its anhydrous form (kokchetavite) in natural rocks, we have synthesized both phases and have characterized them by micro-Raman and NMR spectroscopy. K-cymrite was synthesized at 5 GPa and 800 degrees C. Kokchetavite was obtained by dehydrating K-cymrite at ambient pressure and 550 degrees C. The H-1 MAS and H-1-Si-29 CP MAS NMR spectra of K-cymrite are consistent with the reported crystal structure that contains H2O molecules and has a disordered Si-Al distribution. The Raman spectra obtained under ambient conditions for K-cymrite (and kokchetavite) contain major peaks at 114.0 (109.1), 380.2 (390.0) and 832.5 (835.8) cm(-1). For K-cymrite, OH stretching vibration is also observed at 3541 cm(-1) with a shoulder at 3623 cm(-1). The Raman spectrum for kokchetavite is consistent with that previously reported for a natural sample found as inclusions in clinopyroxenes and garnets in a garnet-pyroxene rock. However, the data for K-cymrite are inconsistent with the Raman features of a previously reported "relict K-cymrite in K-feldspar" from an eclogite. Pressure- and temperature-dependencies of the Raman shifts for the strongest peak of both phases are also reported.

    DOI: 10.2465/jmps.111020i

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  • A neutron/X-ray diffraction, IR, and H-1/Si-29 NMR spectroscopic investigation of armenite: Behavior of extra framework Ca cations and H2O molecules in microporous silicates

    Charles A. Geiger, G. Diego Gatta, Xianyu Xue, Garry J. McIntyre

    ZEITSCHRIFT FUR KRISTALLOGRAPHIE-CRYSTALLINE MATERIALS   227 ( 7 )   411 - 426   2012年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:WALTER DE GRUYTER GMBH  

    The crystal chemistry of armenite, ideally BaCa2Al6Si9O30 center dot 2 H2O, from Wasenalp, Valais, Switzerland was studied. Armenite typically forms in relatively low-temperature hydrothermal veins and fissures and has small pores containing Ca cations and H2O molecules as extra-framework species. Single-crystal neutron and X-ray diffraction measurements were made on armenite from the above locality for the first time. IR powder spectroscopic measurements were made from room temperature (RT) down to 10 K. H-1 and Si-29 NMR measurements were made at RT. Attention was given to investigating the behavior of the extra-framework species and hydrogen bonding. The diffraction results show new features not observed before in published diffraction studies on armenite crystals from other localities. The neutron results also give the first static description of the protons, allowing bond distances and angles relating to the H2O molecules and H-bonds to be determined. The diffraction results indicate Al/Si order in the framework. Four crystallographically independent Ca and H2O molecule sites were refined, whereby both sites appear to have partial occupancies such that locally a Ca atom can have only a single H2O molecule bonded to it through an ion-dipole interaction. The Ca cation is further bonded to six O atoms of the framework forming a quasi cluster around it. The IR spectrum of armenite is characterized in the OH-stretching region at RT by two broad bands at roughly 3470 and 3410 cm(-1) and by a single H2O bending mode at 1654 cm(-1). At 10K four intense OH bands are located at 3479, 3454, 3401 and 3384 cm(-1) and two H2O bending modes at 1650 and 1606 cm-(1). The (29)si MAS NMR spectra show four resonances at -81.9, -83.2, -94.9 and -101.8 ppm that are assigned to crystallographically different Si sites in an ordered structure, although their relative intensities deviate somewhat from those predicted for complete Al/Si order. The H-1 MAS spectra contain a single main resonance near 5.3 ppm and a smaller one near 2.7 ppm, which can be assigned to H2O molecules bonded to Ca and a second H2O type located in a partially occupied site, respectively. Bonding for the extra-framework "Ca-oxygen-anion-H2O-molecule quasi-clusters" and also the nature of H-bonding in the microporous zeolites scolecite, wairakite and episilbite are analyzed. The average OH stretching wavenumbers shown by the IR spectra of armenite and scolecite are, for example, not far removed from that observed in liquid H2O, but greater than that of ice. What remains poorly understood in microporous silicates is how the ion-dipole interaction in quasi clusters affects H-bonding strength between the H2O molecules and the aluminosilicate framework.

    DOI: 10.1524/zkri.2012.1515

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  • Structures of two new high-pressure forms of AlPO4 by X-ray powder diffraction and NMR spectroscopy

    Masami Kanzaki, Xianyu Xue, Sindy Reibstein, Eleanor Berryman, Seonyi Namgung

    ACTA CRYSTALLOGRAPHICA SECTION B-STRUCTURAL SCIENCE   67 ( 1 )   30 - 40   2011年2月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:WILEY-BLACKWELL  

    The crystal structures of two new high-pressure AlPO4 phases are reported. One phase synthesized at 6 GPa and 1523 K is triclinic (P (1) over bar) whilst the other phase synthesized at 7 GPa and 1773 K is monoclinic (P2(1)/c). P-31 MAS (magic-angle spinning) NMR suggests three tetrahedral P sites with equal abundance in both phases. Al-27 3Q MAS NMR spectra provided evidence for two octahedral sites and one five-coordinated Al site in each phase. The crystal structures were solved using an ab initio structure determination technique from synchrotron powder X-ray diffraction data utilizing the local structural information from NMR, and were further refined by the Rietveld method. Both phases contain doubly bent chains made of six edge-shared Al polyhedra (including five-coordinated Al), which are joined by PO4 tetrahedra. The P (1) over bar phase is isostructural with FeVO4 and AlVO4. The two phases differ in the packing manner of the chains. This study has demonstrated that the combined application of ab initio structure determination via X-ray powder diffraction and solid-state NMR spectroscopy is a powerful approach to the rapid solution of complex inorganic crystal structures.

    DOI: 10.1107/S0108768110051050

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  • Determination of J coupling constants between spin-1/2 and quadrupolar nuclei in inorganic solids from spin echo and refocused INEPT experiments: A case study on AlPO4 berlinite

    Xianyu Xue

    SOLID STATE NUCLEAR MAGNETIC RESONANCE   38 ( 2-3 )   62 - 73   2010年9月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ACADEMIC PRESS INC ELSEVIER SCIENCE  

    A systematic study utilizing rotor-synchronized homonuclear (P-31, Al-27) and heteronuclear ({P-31}Al-27 and (Al-27)P-31) spin echo, and {Al-27}P-31 refocused INEPT experiments (employing soft pulses for selective excitation of the central transition for the quadrupolar Al-27 (I=5/2)) have been performed on AlPO4 berlinite at 30 kHz MAS to better understand the J modulation behavior involving half-integer quadrupolar nuclei in solid materials with framework structure. Analyses of the J modulation on either the Al-27 or P-31 coherence in both the {P-31}Al-27 and {Al-27}P-31 spin echo experiments, and both periods of the refocused INEPT experiment yield consistent results for the (2)J(AlP)(Al-O-P) coupling constant (ca. 25 Hz). It is noted that the coupling of each Al-27 to four P-31 spins during the first (Al-27) evolution period of the refocused INEPT, and the populations of P-31 coupled to different numbers (0-4) of Al-27 in the +/- 1/2 Zeeman states during P-31 coherence evolution, which have been neglected in previous studies, must be taken into account for proper treatment. Analysis off modulation on the spin (Al-27) coupled to spin-1/2 nuclei in general gives more accurate results. Weak long-range homonuclear (4)J(PP)(P-O-Al-O-P) coupling was also observed from the P-31 spin echo and INADEQUATE experiments. (C) 2010 Elsevier Inc. All rights reserved.

    DOI: 10.1016/j.ssnmr.2010.09.001

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  • Unique crystal chemistry of two polymorphs of topaz-OH: A multi-nuclear NMR and Raman study

    Xianyu Xue, Masami Kanzaki, Hiroshi Fukui

    AMERICAN MINERALOGIST   95 ( 8-9 )   1276 - 1293   2010年8月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:MINERALOGICAL SOC AMER  

    A new polymorph of topaz-OH (denoted as topaz-OH H) was recently discovered at higher P-T conditions than has been known thus far (denoted as topaz-OH I). High-resolution H-1, Si-29, and Al-27 nuclear magnetic resonance (NMR) and micro-Raman spectroscopy are applied to shed light on the crystal chemistry of both polymorphs. Topaz-OH I, synthesized at 7 GPa and 640 degrees C, is stoichiometric (Si/Al = 0.5) with a largely ordered local structure. Higher P-T topaz-OH I synthesized at conditions close to the polymorphic phase transition boundary, on the other hand, shows lower Si/Al ratios (0.44-0.45) and greater local structural disorder [including a small fraction (similar to 3%) of octahedral Si with a unique Si-29 chemical shift near 133 ppm]. The latter may be accounted for by the development of defects (Si/Al in normally vacant octahedral sites and vacancies in the tetrahedral sites) at higher P-T conditions. Topaz-OH II synthesized at 13.5 similar to 14 GPa and 1300 similar to 1400 degrees C similarly exhibits low Si/Al ratios (0.41-0.46). The NMR and Raman spectra for these topaz-OH II are, in general, broader and revealed a substantial fraction (33-37%) of octahedral Si with a range of Si-29 chemical shifts (-130 to -190 ppm), a small fraction (2-3%) of tetrahedral Al, and a range of (and overall shorter) hydrogen-bonding distances than topaz-OH I. Therefore, the phase transition from topaz-OH I to II is characterized by both a significant increase in the occupied octahedral/tetrahedral site ratio as well as disordering of cation distribution, which is unique from the viewpoint of crystal chemistry.

    DOI: 10.2138/am.2010.3471

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  • The partial H-1 NMR spectra of Al-OH and molecular H2O in hydrous aluminosilicate glasses: Component-Resolved analysis of Al-27-H-1 cross polarization and H-1 spin-echo MAS NMR spectra

    Wim J. Malfait, Xianyu Xue

    SOLID STATE NUCLEAR MAGNETIC RESONANCE   37 ( 3-4 )   60 - 68   2010年5月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ACADEMIC PRESS INC ELSEVIER SCIENCE  

    The Component-Resolved methodology was applied to H-1 spin-echo and Al-27-H-1 cross polarization (CP) MAS NMR data of aluminosilicate glasses. The method was able to resolve two components with different T2 relaxation rates, hydroxyl groups (OH) and molecular water (H2Omol), from the spin-echo data and to determine partial spectra and the relative abundances of OH and H2Omol. The algorithm resolved two to three components with different Al-27-H-1 CP dynamics from the Al-27-H-1 cross polarization data; the obtained partial NMR spectra for Al-OH are in excellent agreement with those obtained previously from the difference spectra between spectra with various contact times and confirm previous quantitative results and models for the Al-OH, Si-OH and H2Omol speciation (Malfait and Xue, 2010). (C) 2010 Elsevier Inc. All rights reserved.

    DOI: 10.1016/j.ssnmr.2010.04.002

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  • The nature of hydroxyl groups in aluminosilicate glasses: Quantifying Si-OH and Al-OH abundances along the SiO2-NaAlSiO4 join by H-1, Al-27-H-1 and Si-29-H-1 NMR spectroscopy

    Wim J. Malfait, Xianyu Xue

    GEOCHIMICA ET COSMOCHIMICA ACTA   74 ( 2 )   719 - 737   2010年1月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:PERGAMON-ELSEVIER SCIENCE LTD  

    The combined results of Al-27-H-1 and H-1-Si-29-H-1 cross polarization NMR experiments for hydrous glasses (containing 0.5-2 wt% water) along the SiO2-NaAlSiO4 join confirm that the dissolution mechanism of water in aluminosilicate glasses is fundamentally the same as for Al-free systems, i.e. the dissolved water ruptures oxygen bridges and creates Si-OH and Al-OH groups, in addition to forming molecular water (H2Omol). The fraction of Al-OH increases non-linearly as the Al content increases with up to half of the OH groups as Al-OH for compositions close to NaAlSiO4. The relative abundances of the different species are controlled by the degree of Al-avoidance and the relative tendency of hydrolysis of the different types of oxygen bridges, Si-O-Si, Si-O-Al and Al-O-Al. A set of homogeneous reactions is derived to model the measured Al-OH/Si-OH speciation, and the obtained equilibrium constants are in agreement with literature data on the degree of Al-avoidance. With these equilibrium constants, the abundance of the different oxygen species, i.e. Si-O-Si, Si-O-Al, Al-O-Al, Si-OH, Al-OH and H2Omol, can be predicted for the entire range of water and Al contents. (c) 2009 Elsevier Ltd. All rights reserved.

    DOI: 10.1016/j.gca.2009.10.036

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  • Proton Distributions and Hydrogen Bonding in Crystalline and Glassy Hydrous Silicates and Related Inorganic Materials: Insights from High-Resolution Solid-State Nuclear Magnetic Resonance Spectroscopy

    Xianyu Xue, Masami Kanzaki

    JOURNAL OF THE AMERICAN CERAMIC SOCIETY   92 ( 12 )   2803 - 2830   2009年12月

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    記述言語:英語   出版者・発行元:WILEY  

    Solid-state 1H nuclear magnetic resonance (NMR) spectroscopy has developed into a versatile, high-resolution method for elucidating the detailed structures of both crystalline and amorphous materials. Here, we summarize our recent endeavors in applying this method to crystalline and glassy silicates and related inorganic materials. We first present updated correlations between 1H chemical shift and O circle dot O and H circle dot O distances of O-H circle dot O hydrogen bonds, derived from a comprehensive 1H chemical shift database containing both original high-quality fast magic angle spinning (MAS) and two-dimensional combined rotation and multiple pulse spectroscopy (CRAMPS)-MAS NMR data and literature MAS NMR data for a large number of inorganic compounds, including phosphates, silicates, (oxy)hydroxides, borates, sulfates, and carbonates. These correlations may be used to estimate hydrogen-bonding distances for inorganic oxide materials of unknown structures. We then present case studies for the application of high-resolution two-dimensional 1H CRAMPS-MAS NMR to unravel the order/disorder of proton distributions in crystalline high-pressure hydrous silicates. Finally, we summarize some of our results on the water speciation in hydrous (alumino)silicate glasses of a range of compositions obtained through comprehensive 1H MAS NMR, and 29Si-1H and 27Al-1H double-resonance NMR experiments, and analyze them in the framework of a quasi-chemical model.

    DOI: 10.1111/j.1551-2916.2009.03468.x

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  • Si-Al distribution in high-pressure CaAl4Si2O11 phase: A Si-29 and Al-27 NMR study

    Xianyu Xue, Shuangmeng Zhai, Masami Kanzaki

    AMERICAN MINERALOGIST   94 ( 11-12 )   1739 - 1742   2009年11月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:MINERALOGICAL SOC AMER  

    High-resolution Si-29 and Al-27 NMR techniques have been applied to resolve the Si-Al distribution and coordination in the high-pressure CaAl4Si2O11 (CAS) phase, a potentially important mineral in subducted crustal materials in the deep mantle that has a unique hexagonal ferrite structure containing two octahedral (M1; M2) and one trigonal bipyramidal sites. The Si-29 MAS NMR spectra of the CAS phase synthesized at 20 GPa and 1400 similar to 1600 degrees C show two broad, asymmetric peaks near -92.7 and -182.7 ppm with an intensity ratio of 1:3, suggesting that 1/4 of the Si are in tetrahedral coordination and 3/4 in octahedral coordination. Therefore, the trigonal bipyramidal and M1 octahedral sites are each occupied by equal proportions of Si and AI, and the former are effectively half-occupied face-sharing tetrahedra (at least for Si). The Al-27 MAS and 3Q MAS NMR spectra contain only one unresolved peak typical of octahedral Al with a range of quadrupolar coupling constants.

    DOI: 10.2138/am.2009.3348

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  • Water speciation in hydrous silicate and aluminosilicate glasses: Direct evidence from Si-29-H-1 and Al-27-H-1 double-resonance NMR

    Xianyu Xue

    AMERICAN MINERALOGIST   94 ( 2-3 )   395 - 398   2009年2月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:MINERALOGICAL SOC AMER  

    Through a combination of H-1 MAS NMR, H-1 -> Si-29 -> H-1 double cross-polarization (CP) MAS NMR and Al-27 -> H-1 CP MAS NMR, different OH species [SiOH, AlOH, and (Ca,Mg)OH (free OH)] have been unambiguously identified for hydrous Ca,Mg-(alumino)silicate glasses. This confirms my earlier speciation assignments made partially on the basis of H-1 chemical shift arguments. The dissoution mechanisms of water in both Al-free silicate and aluminosilicate glasses (quenched melts) are fundamentally similar. For relatively polymerized compositions, it involves dominantly the formation of TOH species (T: Si, Al) through the rupture of T-O-T linkages, in addition to molecular H2O; for more depolymerized compositions containing network-modifying cations of large field strength (e.g., Ca, Mg), free Oil species are also important.

    DOI: 10.2138/am.2009.3088

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  • Dense hydrous magnesium silicates, phase D, and superhydrous B: New structural constraints from one- and two-dimensional Si-29 and H-1 NMR

    Xianyu Xue, Masaw Kanzak, Anton Shatskiy

    AMERICAN MINERALOGIST   93 ( 7 )   1099 - 1111   2008年7月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:MINERALOGICAL SOC AMER  

    To gain new structural insights into phase D and superhydrous B, two phases of potential mantle water reservoir, we have applied a range of one- (1D) and two-dimensional (2D) H-1 and Si-29 NMR techniques, as well as Raman spectroscopy, to samples synthesized at 24 GPa and 900 similar to 1100 degrees C. These data have revealed that phase D is characterized by disordered and varying local structures around both Si and H. The Si-29 NMR spectra of phase D contain a nearly symmetric, broad peak near -177.7 ppm, attributable to octahedral Si with local structural disorder. The high-resolution H-1 CRAMPS spectra of phase D contain a main broad peak near 12.6 ppm with shoulders near 10 and 7 ppm, suggesting a distribution of hydrogen bonding distances. For superhydrous B, our comprehensive 2D H-1 and Si-29 NMR results have clearly revealed that it contains dissimilar hydrogen (H1-H2) pairs and one tetrahedral Si site, consistent with space group Pnn2.

    DOI: 10.2138/am.2008.2751

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  • Structure of hydrous aluminosilicate glasses along the diopside-anorthite join: A comprehensive one- and two-dimensional H-1 and Al-27 NMR study

    Xianyu Xue, Masami Kanzaki

    GEOCHIMICA ET COSMOCHIMICA ACTA   72 ( 9 )   2331 - 2348   2008年5月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:PERGAMON-ELSEVIER SCIENCE LTD  

    We have taken a systematic approach utilizing advanced solid-state NMR techniques to gain new insights into the controversial issue concerning the dissolution mechanisms of water in aluminosilicate melts (glasses). A series of quenched anhydrous and hydrous (similar to 2 wt% H2O) glass samples along the diopside (Di, CaMgSi2O6) - anorthite (An, CaAl2Si2O8) join with varying An components (0, 20, 38, 60, 80, and 100 mol%) have been studied. A variety of NMR techniques, including one-dimensional (ID) H-1 and Al-27 MAS NMR, and Al-27 -> H-1 cross-polarization (CP) MAS NMR, as well as two-dimensional (M) H-1 double-quantum (DQ) MAS NMR Al-27 triple-quantum (3Q) MAS NMR, and Al-27 -> H-1 heteronuclear correlation NMR (HETCOR) and 3QMAS/HETCOR NMR, have been applied. These data revealed the presence of SiOH, free OH ((Ca,Mg)OH) and AlOH species in the hydrous glasses, with the last mostly interconnected with Si and residing in the more polymerized parts of the structure. Thus, there are no fundamental differences in water dissolution mechanisms for Al-free and Al-bearing silicate melts (glasses), both involving two competing processes: the formation of SiOH/AlOH that is accompanied by the depolymerization of the network structure, and the formation of free OH that has an opposite effect. The latter is more important for depolymerized compositions corresponding to mafic and ultramafic magmas.Aluminum is dominantly present in four coordination (Al-IV), but a small amount of five-coordinate Al (Al-V) is also observed in all the anhydrous and hydrous glasses. Furthermore, six-coordinate Al (Al-VI) is also present in most of the hydrous glasses. As Al of higher coordinations are favored by high pressure, (AlOH)-O-VI and (AlOH)-O-V may become major water species at higher pressures corresponding to those of the Earth's mantle. (c) 2008 Elsevier Ltd. All rights reserved.

    DOI: 10.1016/j.gca.2008.01.022

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  • High-pressure delta-AI(OH)(3) and delta-A1OOH phases and isostructural hydroxides/oxyhydroxides: New structural insights from high-resolution H-1 and Al-27 NMR

    Xianyu Xue, Masami Kanzaki

    JOURNAL OF PHYSICAL CHEMISTRY B   111 ( 46 )   13156 - 13166   2007年11月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:AMER CHEMICAL SOC  

    In order to shed light on the proton distributions and order/disorder in high-pressure delta-Al(OH)(3) and delta-AlOOH phases, two-dimensional, high-resolution H-1 CRAMPS (FSLG)-MAS NMR and Al-27 3QMAS NMR spectra have been obtained. For delta-Al(OH)(3), the H-1 CRAMPS-MAS NMR revealed two peaks with an intensity ratio close to 2:1. The Al-27 MAS and 3QMAS NMR suggest a single Al site with a well-defined local structure. For delta-AlOOH, the H-1 and Al-27 NMR indicate the presence of a single H and Al site each. These results are consistent with crystal structures refined from X-ray diffraction. For comparison, 1H MAS and CRAMPS-MAS NMR spectra were also obtained for several other hydroxides/oxyhydroxides, including In(OH)(3) and InOOH that have similar structures to delta-Al(OH)(3) and delta-AlOOH, respectively. These data not only provide additional insights into the proton distributions in these important crystal structure classes but also together provide a better defined quantitative correlation between 1H chemical shift and hydrogen-bonding O center dot center dot center dot O distance.

    DOI: 10.1021/jp073968r

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  • Al coordination and water speciation in hydrous aluminosilicate glasses: Direct evidence from high-resolution heteronuclear H-1-Al-27 correlation NMR

    Xianyu Xue, Masami Kanzaki

    SOLID STATE NUCLEAR MAGNETIC RESONANCE   31 ( 1 )   10 - 27   2007年2月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ACADEMIC PRESS INC ELSEVIER SCIENCE  

    dIn order to shed light on the dissolution mechanisms of water in depolymerized aluminosilicate melts/glasses, a comprehensive one(113) and two-dimensional (2D) NMR study has been carried out on hydrous Ca- and Mg-aluminosilicate glasses of a haplobasaltic composition. The applied techniques include 1D H-1 MAS NMR and Al-27 -> H-1 cross-polarization (CP) MAS NMR, and 2D H-1 NOESY and double-quantum (DQ) MAS NMR, Al-27 triple-quantum (3Q) MAS NMR and 27 -> H-1 heteronuclear correlation (HETCOR) and 3QMAS/HETCOR NMR. Ab initio calculations were also performed to place additional constraints on the 1H NMR characteristics of AlOH and Si(OH)AI groups. This study has revealed, for the first time, the presence of free OH (i.e. (Ca, Mg)OH), SiOH and AlOH species, in addition to molecular H2O, in hydrous glasses of a depolymerized alummosilicate composition. The AlOH groups are mostly associated with four-coordinate Al, but some are associated with five- and six-coordinate Al. (c) 2006 Published by Elsevier Inc.

    DOI: 10.1016/j.ssnmr.2006.11.001

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  • Depolymerization effect of water in aluminosilicate glasses: Direct evidence from H-1-Al-27 heteronuclear correlation NMR

    Xianyu Xue, Masami Kanzaki

    AMERICAN MINERALOGIST   91 ( 11-12 )   1922 - 1926   2006年11月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:MINERALOGICAL SOC AMER  

    We have applied one-dimensional (1D) H-1 MAS NMR Al-27 -> H-1 CP MAS NMR, as well as 2D(27)Al triple-quantum (3Q) MAS NMR, Al-21 -> H-1 heteronuclear correlation (HETCOR) and high-resolution 3QMAS/HETCOR NMR techniques to KAlSi3O8 (Or), NaAlSi3O8 (Ab) and NaAlSiO4 (Ne) glasses containing 0 similar to 2 wt% H2O to shed light on the dissolution mechanisms of water in aluminosilicate melts (glasses). An Al Q(3)-OH group, characterized by H-1 chemical shifts of 1.3-1.9 ppm, was identified for all hydrous glasses. Its abundance increases with bulk Al/Si ratio. The Al-27 chemical shifts (partial derivative(Al)(i)) of this species are 64-68 ppm, larger than those of Al Q(4) by 3-6 ppm. Despite this difference, it is only through Al-27 -> H-1 HETCOR and 3QMAS/HETCOR, but not Al-27 MAS or 3QMAS NMR that the peaks are resolved. This study has demonstrated that depolymerization and formation of AlOH/SiOH is a general water dissolution mechanism for polymerized aluminosilicate melts (glasses), and HETCOR NMR experiments involving H-1 are the key to its revelation.

    DOI: 10.2138/am.2006.2365

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  • Cation order and hydrogen bonding of high-pressure phases in the Al2O3-SiO2-H2O system: An NMR and Raman study

    Xianyu Xue, Masami Kanzaki, Hiroshi Fukui, Eiji Ito, Takafumi Hashimoto

    AMERICAN MINERALOGIST   91 ( 5-6 )   850 - 861   2006年5月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:MINERALOGICAL SOC AMER  

    Topaz-OH, phase egg, and delta-AIOOH are hydrous phases in the Al2O3-SiO2-H2O system that have been found to be stable at successively higher pressures up to those corresponding to the lower mantle, and thus they may be important water reservoirs in the deep mantle. We have applied H-1, Si-29, and Al-27 nuclear magnetic resonance (NMR) and Raman spectroscopy to shed new light on the structure of these phases. Si-29 and (27)AI NMR results clearly revealed that the Si-Al distribution in phase egg is partially disordered. The presence of structural disorder in topaz-OH was also confirmed. H-1 NMR and Raman data are both consistent with strong, but asymmetric hydrogen bonding in delta-AlOOH and phase egg, and a range of hydrogen bonding distances in topaz-OH. The observed structural disorder and hydrogen bonding could be responsible for the high upper temperature stability limits (1500 similar to 1700 degrees C) of phase egg and topaz-OH, and are also relevant to the incorporation mechanisms of water in nominally anhydrous stishovite.

    DOI: 10.2138/am.2006.2064

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  • Al2O3-SiO2-H2O系高圧相のカチオン秩序度及び水素結合

    薛 献宇, 神崎 正美, 福井 宏之, 伊藤 英司, 橋本 崇史

    日本鉱物学会年会講演要旨集   2005   45 - 45   2005年

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    出版者・発行元:日本鉱物科学会  

    Topaz-OH (Al2SiO4(OH)2), phase egg (AlSiO3OH) and delta-AlOOH are hydrous phases in the Al2O3-SiO2-H2O system that have been found to be stable at successively higher pressures up to those of the lower mantle, and thus may be important in the siliceous sediments of subducting slab. Although the crystal structures of these phases have been determined by X-ray diffraction, this technique is insensitive to H positions and Al-Si disorder. We have applied 1H, 29Si and 27Al NMR and micro-Raman spectroscopy to gain additional insights. Our study revealed that the octahedral Al-Si distribution in phase egg is partially disordered, which is expected to have a significant effect on its physical and thermodynamic properties and stability field. In addition, these data also suggest the presence of some structural disorder in topaz-OH. Finally, our data support that hydrogen bonding is strong in phase egg and delta-AlOOH, but weak in topaz-OH.

    DOI: 10.14824/kobutsu.2005.0.45.0

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  • 第一原理電場勾配計算とNMRへの応用

    神崎 正美, 薛 献宇

    日本鉱物学会年会講演要旨集   2005   23 - 23   2005年

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    出版者・発行元:日本鉱物科学会  

    従来NMR分光法では化学シフトが主に構造の解釈に使われてきたが,非1/2スピンを持つ核では核四極子結合常数(Cq)と非対称性因子(eta)も局所構造の情報を持っている.サイト同定等のためにこれらのパラメータを結晶構造から予測する必要性が高まっている.本研究では第一原理計算法を使って様々な結晶におけるEFGとetaの計算を行うことを試み,実験データと比較した.第一原理計算にはfull potential LAPW法プログラムであるWIEN2kを使った.計算されたCqとNMRから得られたCqは水素を含む系を除いてよく一致した.またetaについても同様である.本研究から第一原理計算により十分な精度でCqとetaを予測できることがわかった.

    DOI: 10.14824/kobutsu.2005.0.23.0

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  • NMR characteristics of possible oxygen sites in aluminosilicate glasses and melts: an ab initio study

    Xue, X, M. Kanzaki

    J. Phys. Chem. B   103   10816 - 10830   1999年

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  • Correlations between 29Si, 17O and 1H NMR properties and local structures in silicates - an ab initio calculation

    X. Xue, M. Kanzaki

    Phys. Chem. Mineral.   26   14 - 30   1998年

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  • Correlations between 17O NMR parameters and local structure around oxygen in high-pressure silicates : Implications for the structure of silicate melts at high pressures(共著)

    X. Xue, J.F. Stebbins, M. Kanzaki

    American Mineralogist   79 ( 1-2 )   31 - 42   1994年1月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

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  • A SI-29 MAS NMR-STUDY OF SUB-TG AMORPHIZATION OF STISHOVITE AT AMBIENT PRESSURE 査読

    XY XUE, JF STEBBINS, M KANZAKI

    PHYSICS AND CHEMISTRY OF MINERALS   19 ( 7 )   480 - 485   1993年2月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:SPRINGER VERLAG  

    Stishovite, a high-pressure SiO2 polymorph in which each Si is coordinated by six O atoms, transforms to an amorphous phase when undergoing heat treatment below the glass transition temperature at ambient pressure. We have applied Si-29 magic angle spinning nuclear magnetic resonance spectroscopy (MAS NMR) to study this amorphization process. We found that the amorphous phase generated after heating stishovite for up to 3 days at around 600-degrees-C consisted exclusively of four-coordinate Si, similar to glasses quenched from melts at ambient pressure. Furthermore, our data suggest that there are subtle structural differences between the amorphous phase transformed from stishovite at 600-degrees-C and glasses quenched from melts at ambient pressure: the amorphous phase from stishovite had a smaller mean Si-O-Si angle initially, and it gradually relaxed toward the latter with increasing heating time. There was no detectable change in the stishovite structure even after about 80% of it had been converted to the amorphous phase. The mechanism of the amorphization of stishovite is discussed in light of these results.

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  • THE CRYSTAL-STRUCTURE OF A NEW HIGH-PRESSURE POLYMORPH OF NA2SI2O5 査読

    BD SANTARSIERO, XY XUE, M KANZAKI

    PROCEEDINGS OF THE SYMPOSIUM ON THE STRUCTURAL CHEMISTRY OF SILICATES   27   279 - 283   1993年

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)   出版者・発行元:AMER CRYSTALLOGRAPHIC ASSOC  

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  • Characterization of crystalline and amorphous silicates quenched from high pressure by 29Si MAS NMR spectroscopy (共著)

    M. Kanzaki, J.F. Stebbins, X. Xue

    HIgh-Pressure Research: Application to Earth and Planetary Sciences (Y. Syono and M.H. Manghnani eds), Terra Sci. Pub./Tokyo   89 - 100   1992年

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  • Characterization of Quenched High Pressure Phases in CaSiO3 system by XRD and 29Si NMR (共著)

    M. Kanzaki, J.F. Stebbins, X. Xue

    Geophysical Research Letters   18 ( 3 )   463 - 466   1991年3月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1029/91GL00463

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  • Pressure-Induced Silicon Coordination and Tetrahedral Structural Changes in Alkali・Oxide-Silica Melts up to 12 GPa : NMR, Raman, and Infrared Spectroscopy (共著)

    X. Xue, J.F. Stebbins, M. Kanzaki, P.F. McMillan, B. Poe

    American Mineralogist   76 ( 1-2 )   8 - 26   1991年1月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

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  • Silicon coordination and speciation changes in a silicate liquid at high pressures (共著)

    X. Xue, J.F. Stebbins, M. Kanzaki, R.G. Tronnes

    Science   245 ( 4921 )   962 - 964   1989年9月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1126/science.245.4921.962

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  • Baを取り込んだカルサイト中の炭酸イオンの挙動

    丸形 詩歩, 鍵 裕之, 小松 一生, 斉藤 綾花, 薛 献宇, 杉山 和正

    日本地球化学会年会要旨集   67   99   2020年

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    記述言語:日本語   出版者・発行元:一般社団法人日本地球化学会  

    Baを取り込んだカルサイトの挙動について報告する。粉末X線回折パターンにおいて、Ba/(Ca+Ba) = 0.25以上で113反射が消失した。純粋なカルサイトでは1250 K付近で113反射が消失し、炭酸イオンの回転無秩序化に起因する可能性が報告されている。しかし、本研究では91 Kでも113反射が消失し、DSCで回転無秩序化に相当する熱の出入りが検出されなかった。また、Baを含むカルサイトの13C MAS NMRスペクトルや赤外吸収スペクトルの結果は、Baを含むカルサイトでは各炭酸イオン周辺のカチオン分布が異なり、Ba濃度の増加に伴って炭酸イオンの対称性が低下することを示している。以上の結果より、Baを含むカルサイト中の炭酸イオンは回転無秩序状態ではなく、静的無秩序状態であることが強く示唆される。

    DOI: 10.14862/geochemproc.67.0_99

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  • (Mg,Zn)2SiO4オリビン固溶体におけるカチオンの分布:29Si MAS NMR及び第一原理計算による解明

    薛 献宇, 神崎 正美

    日本鉱物科学会年会講演要旨集   2015   77   2015年

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    記述言語:日本語   出版者・発行元:一般社団法人日本鉱物科学会  

    (Mg,Zn)2SiO4オリビン固溶体について、第一原理計算と29Si MAS NMR測定を行い、M1, M2席へのZnの分布と29Si MAS NMRの化学シフトの関係を調べた。その結果、29Si MAS NMRからZnのM1, M2席への分配に関する定量的な情報が得られることが確認できた。これはオリビンのSi四面体は2つのM1八面体及び1つのM2八面体と綾を共有し、2つのM1八面体及び4つのM2八面体と角を共有するが、その29Si化学シフトは綾共有八面体席におけるZnの置換に最も敏感で、かつM1かM2かによって異なるためである。ZnはM1席を優先的に占有していることも分かった。同様なアプローチは他のカチオン(e.g. H)の分布の解明にも有効であろう。

    DOI: 10.14824/jakoka.2015.0_77

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  • ケイ酸塩メルト (ガラス) における炭酸塩の化学種 : ab initio 計算とNMR測定からの新しい知見

    薛 献宇, 神崎 正美

    日本鉱物科学会年会講演要旨集   2013   37   2013年9月

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    記述言語:日本語   出版者・発行元:一般社団法人日本鉱物科学会  

    CO2のケイ酸塩メルト/ガラスの性質へ及ぼす効果を理解するには、その溶解機構の解明が必要不可欠である。CO2は、分子CO2 と炭酸塩イオン(CO32) の形でメルト中に溶け込んでいることが知られている。しかし、CO32 はどのようにメルト構造に取り込まれているのか、ネットワーク構造へどのような影響をもたらすかは良く分かっていない。本研究ではab initio計算(振動周波数、13C化学シフトテンソル)及びのCO2を含む異なったケイ酸塩組成の急冷ガラスの多核種NMR測定を行なった。計算から、振動周波数と13C化学シフトテンソルは共にCO32-の局所構造に敏感であるが分かった。実験データは、CO32は重合度の低いメルトでは主にネットワークと繋がっていないfree CO32として重合度の高い組成では2つのSi/AlとつながるネットワークCO32 として存在することを示唆する。

    DOI: 10.14824/jakoka.2013.0_35

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  • アルカリケイ酸塩メルト(ガラス)における水の溶解機構 : ^<29>Si-^1Hと^<23>Na-^1H二重共鳴NMRによる解明

    薛 献宇, 神崎 正美

    日本鉱物科学会年会講演要旨集   2012   28 - 28   2012年9月

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    記述言語:英語   出版者・発行元:一般社団法人日本鉱物科学会  

    水のケイ酸塩メルト/ガラスの性質へ及ぼす効果を理解するには、水の溶解機構の解明が必要不可欠である。Ca-Mgケイ酸塩メルト/ガラスにおいては、我々のこれまでの研究から、水は分子H2Oのほか、メルトのネットワーク構造や粘性に相反の効果を及ぼすSiOHとfree OH (e.g. MgOH)種として存在することが分かった。一方で、アルカリケイ酸塩系においてはfree OHの存在は未だに議論されている。本研究では1H MAS NMRと29Si-1H と 23Na-1H二重共鳴NMRの組み合わせにより、Naケイ酸塩メルト/ガラスには水は主にメルト構造の重合度や粘性を下げる効果のあるSiOH種及び分子H2Oとして存在することを明らかにした。

    DOI: 10.14824/jakoka.2012.0_27

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  • K-cymrite の構造と特異な^<29>Si NMR特徴

    薛 献宇, 神崎 正美

    日本鉱物科学会年会講演要旨集   2011   197 - 197   2011年9月

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    記述言語:英語   出版者・発行元:一般社団法人日本鉱物科学会  

    29Si MAS NMRはケイ酸塩鉱物におけるSi-Al分布の定量的解析に最も有効な手段である。テクトアルミノ珪酸塩鉱物においては一般的に特定のTサイトに対して、nSi(4-n)Al(n=0-4)と連結するSi(Si(nSi))に対応する最大5つの29Si MAS NMRピークがありうると考えられてきた。本研究では5GPa, 800˚C合成した29Si濃縮したK-cymrite (KAlSi3O8.H2O)高圧相のNMR結果を報告する。K-cymrite は(Si,Al)O4四面体(Q4)からなる2重層構造を有する。しかし、一つのTサイトにもかかわらず、5つ以上の29Si MAS NMRピークが観測された。2次元J結合を利用したNMR測定により、これらはK-cymrite中のSi(nSi)(n=1 to 4)に対応し、Si(3Si) と Si(2Si)はそれぞれ二つのT-O-T角の存在により二つのピークを示すことが分かった。

    DOI: 10.14824/jakoka.2011.0.193.0

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  • K-cymrite(KAlSi_3O_<8^*>H_2O) とその無水相のラマン分光

    神崎 正美, 薛 献宇, AMALBERTI Julien, ZHANG Qian

    日本鉱物科学会年会講演要旨集   2011   56 - 56   2011年9月

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    記述言語:日本語   出版者・発行元:一般社団法人日本鉱物科学会  

    超高圧変成岩中のK-cymrite (KAlSi3O8*H2O)とその無水相(kokchetavite)の顕微ラマンによる同定を助けるために、各合成相のラマン測定を行った。K-cymriteは5 GPa, 800 Cで合成、kokchetaviteはK-cymriteを加熱脱水して得た。K-cymriteとkokchetaviteのメインピークのラマンシフトはそれぞれ380と390 cm-1であった。この結果からは、最近報告された天然のK-cymrite (Zhang et al., AM, 2009) が実際にはkokchetaviteである可能性が高いと推定された。さらにダイヤモンドアンビルセルを使って高圧下のラマンスペクトルを測定した。K-cymriteとkokchetaviteのメインピークの圧力依存性は4.9と5.6 cm-1/GPaであった。

    DOI: 10.14824/jakoka.2011.0.54.0

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  • Topaz-OH の相転移と結晶化学的特徴

    薛 献宇, 神崎 正美

    日本鉱物科学会年会講演要旨集   2010   72 - 72   2010年9月

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    記述言語:英語   出版者・発行元:一般社団法人日本鉱物科学会  

    Topaz-OH (理想式: Al2SiO4(OH)2)の新しい高圧相(topaz-OH II)を発見した。その安定領域は放射光を用いたその場観察から、従来知られているtopaz-OH相 (topaz-OH I)に比べてより高温高圧(13-14 GPa, 1300-1500℃)側にあることが分かった。その結晶構造は粉末X線回折法で決定した。二つのtopaz-OH相の結晶化学的特徴についても、詳細な多核・高分解能NMR及び顕微ラマン分光法によって解明した。

    DOI: 10.14824/jakoka.2010.0.70.0

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  • Water speciation in hydrous (alumino)silicate melts/glasses and quasi-chemical modeling

    X. Xue, M. Kanzaki, W. J. Malfait

    GEOCHIMICA ET COSMOCHIMICA ACTA   74 ( 12 )   A1165 - A1165   2010年6月

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    記述言語:英語   掲載種別:研究発表ペーパー・要旨(国際会議)   出版者・発行元:PERGAMON-ELSEVIER SCIENCE LTD  

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  • NMRと粉末X線回折法によるAlPO_4高圧相の構造解析

    神崎 正美, 薛 献宇

    日本鉱物科学会年会講演要旨集   2009   131 - 127   2010年4月

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    記述言語:日本語   出版者・発行元:一般社団法人日本鉱物科学会  

    AlPO4の6∼7GPa付近の高圧急冷実験から1000°C付近でI相,1500°C付近でII相を新たに見いだした.両相の構造をNMRと粉末X線回折法で調べた.31P MAS NMRからは各相とも3種で同比率の4配位P席があり,27Al MQ MAS NMRからは各相それぞれ2種の6配位Al席と1種の5配位Al席があることが分かった(同比率).粉末X線回折データの解析には実空間のモンテカルロ探索法(FOX)を使い,NMRから得られた配位数と席数を多面体モデル作成に活用した.I相が空間群P-1, II相がP21/c,a,c軸はほぼ同じでIIのb軸がIの約2倍であった.密度は両相ほぼ同じで,常圧相からは約28%増となる.結晶構造は両相ともに,稜を共有した6個のAl多面体による短鎖がPO4四面体でつなぎあわされて,3次元ネットワークを形成している.

    DOI: 10.14824/jakoka.2009.0.127.0

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  • 含水ケイ酸塩メルト・ガラスにおける含水種の分布と準化学モデリング

    XUE Xianyu

    2009   132   2010年4月

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  • 含水珪酸塩ガラス/メルトのおける含水種の分布と準化学モデリング

    薛 献宇

    日本鉱物科学会年会講演要旨集   2009   128 - 128   2009年

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    記述言語:日本語   出版者・発行元:一般社団法人日本鉱物科学会  

    我々は近年高度な固体NMR測定法を広い組成範囲の含水ガラスへ応用することにより、(アルミノ)ケイ酸塩メルトにおける水の溶解機構を解明しつつある。H2O分子の他に、Si-OH, Al-OH, free OH (e.g. Mg-OH)も存在することが分かった。それらの分布はメルトの組成に強く依存し、メルトにおける各種無水・含水酸素種間の化学反応(準化学平衡)で説明できる。

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  • 多核種・多次元固体NMR分光法の魅力 ―含水高圧鉱物・含水アルミノケイ酸塩ガラスを例に―

    薛 献宇, 神崎 正美

    地球化学   42 ( 4 )   133 - 155   2008年

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    記述言語:日本語   出版者・発行元:日本地球化学会  

    Knowledge of the atomic structures of Earth's materials is indispensible for the understanding/modeling of macroscopic geochemical processes. Solid-state NMR spectroscopy offers a rich variety of advanced multi-nuclear, multi-dimensional techniques that can provide not only quantitative information about local structures around different elements (isotopes), but also direct information concerning atomic connectivities. Recently, we have applied some of these techniques to unravel the structures of (1) high-pressure hydrous minerals in the MgO-SiO2-H2O and Al2O3-SiO2-H2O systems (e.g. phase egg, δ-AlOOH, phase D, superhydrous B), which represent potential water reservoirs in the Earth's mantle, and (2) hydrous (alumino) silicate glasses (quenched melts), which serve as analogs for natural magmas. For the hydrous minerals, the states of Si-Al and Si-Mg order/disorder among octahedral sites and hydrogen distribution and hydrogen-bonding distances were clearly revealed. Such information would have been difficult to obtain by any other single technique. For the hydrous aluminosilicate melts, advanced NMR techniques provided the key information needed to end a long-standing controversy concerning the water dissolution mechanisms. Some of these results are summarized here to demonstrate the usefulness and wonder of advanced solid-state NMR spectroscopy.

    DOI: 10.14934/chikyukagaku.42.133

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  • 高圧含水マグネシウムケイ酸塩D相及び superhydrous B 相の構造 : 1・2次元^1H、^<29>Si NMRによる情報

    薛 献宇, 神崎 正美, SHATSKIY Anton

    日本鉱物学会・学術講演会,日本岩石鉱物鉱床学会学術講演会講演要旨集   2007   133 - 133   2007年9月

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    記述言語:英語   出版者・発行元:一般社団法人日本鉱物科学会  

    DOI: 10.14824/jakoka.2007.0.130.0

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  • 高圧delta-Al(OH)3とdelta-AlOOH相及び同一構造型In(OH)3とInOOH相中の水素:高分解能1H CRAMPS NMRとRaman分光法からの情報

    薛 献宇, 神崎 正美

    日本セラミックス協会 年会・秋季シンポジウム 講演予稿集   2007F   118 - 118   2007年

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    記述言語:日本語   出版者・発行元:公益社団法人 日本セラミックス協会  

    高圧delta-Al(OH)3とdelta-AlOOH相及び同一構造型In(OH) 3とInOOH相中の水素分布並びに構造秩序度への制約を得るために、高分解能1H CRAMPS NMRとRaman分光法測定を行った。delta-Al(OH) 3とIn(OH)31H CRAMPS NMRスペクトルではそれぞれ二つのピークが見られ、報告された結晶構造と調和する。delta-AlOOHとInOOHの1H CRAMPS NMRスペクトルはそれぞれ一つのピークを与える。特にdelta-AlOOHの線幅(0.6 ppm)がシャープなことから、disorderの可能性が低いと推定できる。それぞれの1H NMR化学シフト並びにOH伸縮振動数は報告された水素結合(O-H…O)距離とよく一致する。ただし、RamanのOH伸縮領域におけるバンドは全て独立したO-H結合の伸縮振動に限らず、Fermi resonanceやO-H振動子間のカップリングによるものもあると思われる。

    DOI: 10.14853/pcersj.2007f.0.118.0

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  • 多核種・多次元固体NMR分光法の鉱物・メルトへの応用

    薛 献宇

    日本地球化学会年会要旨集   54   211 - 211   2007年

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    出版者・発行元:一般社団法人日本地球化学会  

    NMR分光法は個々の元素(核種)の周りの局所構造に関する定量的情報を与えるのみでなく、多様な一次元・多次元測定法を生かすことにより、パラメータの解釈に頼らずに、原子間の繋がり情報を直接引き出せるのが大きな特長である。我々は近年様々な多核種・多次元固体NMR分光法測定法を構造プローブとして、水とケイ酸塩間の相互作用を原子レベルの視点で検証してきた。講演では含水高圧マントル鉱物の構造、含水ケイ酸塩・アルミノ珪酸塩メルト(急冷ガラス)の構造、水和した鉱物の界面構造といった応用例を挙げながら、多核種・多次元固体NMR分光法の魅力を紹介する。

    DOI: 10.14862/geochemproc.54.0.211.0

    CiNii Article

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  • Dissolution mechanisms of water in depolymerized silicate melts: Constraints from 1H and 29Si NMR spectroscopy and ab initio calculations

    X. Xue, M. Kanzaki

    Geochim. Cosmochim. Acta   65   5027 - 5057   2004年

  • The effect of sulfate sulfur on the structure of M2O-SiO2 glasses: A Si-29 MAS NMR Raman and FT-IR study

    T Tsujimaru, Xue, X, MJ Walter, S Yamashita, M Kanzaki

    GEOCHIMICA ET COSMOCHIMICA ACTA   67 ( 18 )   A494 - A494   2003年9月

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    記述言語:英語   掲載種別:研究発表ペーパー・要旨(国際会議)   出版者・発行元:PERGAMON-ELSEVIER SCIENCE LTD  

    Web of Science

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  • The dissolution mechanism of water in alkaline earth silicate and aluminosilicate melts: One view from H-1 MAS NMR

    Xue, X, M Kanzaki

    GEOCHIMICA ET COSMOCHIMICA ACTA   67 ( 18 )   A543 - A543   2003年9月

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    記述言語:英語   掲載種別:研究発表ペーパー・要旨(国際会議)   出版者・発行元:PERGAMON-ELSEVIER SCIENCE LTD  

    Web of Science

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  • The dissolution mechanisms of forsterite and enstatite: Constraints from Si-29 and H-1 MAS NMR

    Xue, X, M Kanzaki, DG Fraser

    GEOCHIMICA ET COSMOCHIMICA ACTA   66 ( 15A )   A853 - A853   2002年8月

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    記述言語:英語   掲載種別:研究発表ペーパー・要旨(国際会議)   出版者・発行元:PERGAMON-ELSEVIER SCIENCE LTD  

    Web of Science

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  • NMR evidence for a new water dissolution mechanism in alkaline earth silicate melts

    M Kanzaki, Xue, X

    GEOCHIMICA ET COSMOCHIMICA ACTA   66 ( 15A )   A382 - A382   2002年8月

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    記述言語:英語   掲載種別:研究発表ペーパー・要旨(国際会議)   出版者・発行元:PERGAMON-ELSEVIER SCIENCE LTD  

    Web of Science

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  • Phase relations in Na2O-SiO2 and K2Si4O9 systems up to 14 GPa and 29Si NMR study of the new high-pressure phases: Implications to the structure of high-pressure silicate glasses

    M. Kanzaki, X. Xue, J.F. Stebbins

    Phys. Earth Planet. Int.   107   9 - 21   1998年

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講演・口頭発表等

  • 鉱物におけるカチオンの秩序度及び水素結合:多核NMR測定及び第一原理計算による解明

    薛献宇

    第61回NMR討論会(2022)  2022年11月9日 

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    開催年月日: 2022年11月8日 - 2022年11月10日

    記述言語:英語   会議種別:口頭発表(一般)  

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  • Ba含有カルサイトにおける炭酸イオンの静的無秩 序状態の実験的証拠

    鍵 裕之, 丸形 詩歩, 伊地知 雄太, 小松 一生, 薛献宇, 杉山 和正

    一般社団法人日本鉱物科学会2022年年  2022年9月19日 

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    開催年月日: 2022年9月17日 - 2022年9月19日

    記述言語:日本語   会議種別:口頭発表(一般)  

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  • ウッシング石(Na2AlSi3O8OH)における Si-Alの配 置と水素結合:多核種 NMR及び第一原理計算による 解明

    薛 献宇

    一般社団法人日本鉱物科学会2022年年会  2022年9月19日 

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    開催年月日: 2022年9月17日 - 2022年9月19日

    記述言語:英語   会議種別:口頭発表(一般)  

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  • 含 Al-CaTiO3ペロブスカイトの構造変化2

    永井 隆哉, 高倉 直樹, 松本 洋輔, 田口 裕宇, 献宇

    一般社団法人日本鉱物科学会2022年年会  2022年9月19日 

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    開催年月日: 2022年9月17日 - 2022年9月19日

    記述言語:日本語   会議種別:口頭発表(一般)  

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  • 含Al-CaTiO3ペロブスカイトの構造変化

    永井 隆哉, 高倉 直樹, 松本 洋輔, 薛 献宇

    日本鉱物科学会2021年年会  2021年9月16日 

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    開催年月日: 2021年9月16日 - 2021年9月18日

    記述言語:日本語   会議種別:口頭発表(一般)  

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  • Baを取り込んだカルサイト中の炭酸イオンの挙動

    丸形 詩歩, 鍵 裕之, 小松 一生, 斉藤 綾花, 薛 献宇, 杉山 和正

    日本地球化学会年会要旨集  2020年  一般社団法人日本地球化学会

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    開催年月日: 2020年

    記述言語:日本語  

    Baを取り込んだカルサイトの挙動について報告する。粉末X線回折パターンにおいて、Ba/(Ca+Ba) = 0.25以上で113反射が消失した。純粋なカルサイトでは1250 K付近で113反射が消失し、炭酸イオンの回転無秩序化に起因する可能性が報告されている。しかし、本研究では91 Kでも113反射が消失し、DSCで回転無秩序化に相当する熱の出入りが検出されなかった。また、Baを含むカルサイトの13C MAS NMRスペクトルや赤外吸収スペクトルの結果は、Baを含むカルサイトでは各炭酸イオン周辺のカチオン分布が異なり、Ba濃度の増加に伴って炭酸イオンの対称性が低下することを示している。以上の結果より、Baを含むカルサイト中の炭酸イオンは回転無秩序状態ではなく、静的無秩序状態であることが強く示唆される。

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  • Hydrogen incorporation mechanism in synthetic katoite-grossular and natural grossular: 1H static and MAS NMR and first-principles calculation

    Goldschmidt 2017  2017年 

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  • Application of High-resolution Solid-State NMR Spectroscopy to Earth And Planetary Materials

    International Symposium Misasa VI  2016年 

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  • Application of High-resolution Solid-State NMR Spectroscopy to Earth And Planetary Materials

    国際シンポジウムMISASA VI “Frontiers in Earth and Planetary Materials Research: Origin, Evolution and Dynamics”  2016年 

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  • Hydrogen incorporation mechanisms in forsterite: 1H NMR measurement and first-principles calculation

    Goldschmidt2016  2016年 

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  • グロッシュラーとフォルステライトにおける4H=1Si置換:NMR分光法及び第一原理計算による解明

    日本鉱物科学会2016年度年会  2016年 

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  • 固体NMRの無機地球物質へ応用

    岡山大学異分野融合研究育成支援事業 シンポジウム 固体NMRの利用促進と異分野連携研究展開  2015年 

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  • Application of Solid-State NMR Spectroscopy to Earth And Planetary Materials: Activity Report and Future Perspective

    国際シンポジウムMISASA V “Comprehensive Exploration of the Solar System: Sample Return and Analysis”  2015年 

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  • Application of Solid-State NMR Spectroscopy to Earth And Planetary Materials: Activity Report and Future Perspective

    International Symposium MISASA V  2015年 

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  • ”無水”鉱物における水の溶解機構:固体NMR及び第一原理計算による解明

    第58回固体NMR・材料フォーラム  2015年 

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  • CO2 speciation in Ca- and Na- aluminosilicate glasses as a function of melt polymerization: A multi-nuclear NMR study

    Goldschmidt 2014  2014年 

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  • NMR crystallography of high-pressure silicate minerals and related inorganic materials

    EUROMAR2013  2013年 

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  • Breakdown of a common notion for 29Si NMR of aluminosilicates: Information from J-resolved and CPMG measurements

    第51回NMR討論会  2012年 

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  • Water speciation in sodium silicate glasses (quenched melts): A comprehensive NMR study

    AGU fall meeting 2012  2012年 

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  • アルカリケイ酸塩メルト(ガラス)におけ る水の溶解機構

    日本鉱物科学会2012年度年会  2012年 

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  • Crystal structures of three new AlPO4 high-pressure phases from powder X-ray diffraction, NMR and first principles calculations, and their unique J-coupling characteristics

    第50回NMR討論会:記念国際シンポジウム  2011年 

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  • K-cymrite (KAlSi3O8.H2O)とその無水相のラマン分光

    日本鉱物科学会年会  2011年 

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  • アルミノ珪酸塩相のSi-29 NMR 特徴:J結合を利用した測定から見た意外な一面

    第50回 固体NMR・材料フォーラム  2011年 

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  • K-cymriteの構造と特異な29Si NMR特徴

    日本鉱物科学会年会  2011年 

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  • Topaz-OHの相転移と結晶化学的特徴

    日本鉱物科学会年会  2010年 

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  • 新しいAlPO4高圧相における高分解能NMRと粉末X線回折による構造決定及び31P-27Alと31P-31P間のJ結合を用いたNMRピークの帰属 2010年5月10日 oral

    第47回 固体 NMR・材料フォーラム  2010年 

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  • Water speciation in hydrous (alumino)silicate melts/glasses and quasi-chemical modeling

    Goldschmidt 2010  2010年 

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  • NMRと粉末X線回折法によるAlPO4高圧相の構造解析

    日本鉱物科学会年会  2009年 

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  • 含水珪酸塩ガラス/メルトのおける含水種の分布と準化学モデリング

    日本鉱物科学会年会  2009年 

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  • Structures of high-pressure hydrous minerals: Insights from one- and two dimensional NMR spectroscopy

    4th Asian Conference on High Pressure Research  2008年 

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  • (逆検知)27Al→1H及び1H→29Si→1H CPMAS NMR法による含水ケイ酸塩・アルミノ珪酸塩ガラス中の含水種の解明

    第44回 /9回の固体 NMR・材料フォーラム  2008年 

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  • Structures of high-pressure hydrous minerals and aluminosilicate melts (glasses): Insights from one- and two-dimensional NMR spectroscopy

    第3回COE-21三朝国際シンポジウムMisasa-III "Origin, Evolution and Dynamics of the Earth,  2008年 

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  • Proton distributions in high-pressure hydrous phases in the Al2O3-SiO2-H2O system: New insights from high-resolution 1H NMR spectroscopy

    Frontiers in Mineral Sciences 2007  2007年 

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  • 1・2次元高分解能1Hと27Al NMRによる各種低圧・高圧オキシ水酸化物・水酸化物相の構造解明

    第42回 /7回の固体 NMR・材料フォーラム  2007年 

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  • 高圧含水鉱物中の水素とSi-Mg-Al分布の秩序性:高度なNMR分光法による情報

    第48回高圧討論会, 2007年11月20日-22日、倉吉 * 薛 献宇・神崎 正美 (2007) 2007年11月20日、Oral, 1B11  2007年 

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  • 多核種・多次元固体NMR分光法の鉱物・メルトへの応用

    日本地球化学会2007年度年会  2007年 

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  • 高圧含水マグネシウムケイ酸塩D相及びsuperhydrous B相の構造:1・2次元1H、29Si NMRによる情報

    日本鉱物科学会2007年度年会  2007年 

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  • Structure of hydrous silicate and aluminosilicate melts (glasses): Insights from one- and two-dimensional 1H and 27Al NMR

    Frontiers in Mineral Sciences 2007  2007年 

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  • 高圧delta-Al(OH)3とdelta-AlOOH相及び同一構造 型In(OH)3とInOOH相中の水素:高分解能1H CRAMPS NMRとRaman分光法からの情報

    日本セラミックス協会 第20回秋季シンポジウム  2007年 

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  • 含水ケイ酸塩・アルミノ珪酸塩メルト(ガラス)の構造解明:1次元及び2次元 1H 、 27Al NMRによる総合的アプローチ

    第4回強磁場固体NMRフォーラム/第39回固体 NMR・材料研究会 合同研究会  2006年 

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  • Structure of hydrous aluminosilicate melts (glasses): ending a long-standing controversy by 1H-27Al HETCOR and 3QMAS/HETCOR NMR

    第45回NMR討論会  2006年 

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  • Structure of hydrous (alumino)silicate melts (glasses): the end of a long-standing controversy

    国際シリケートメルトワークショップ  2006年 

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  • Dissolution mechanisms of water in depolymerized aluminosilicate melts (glasses): a comprehensive one- and two-dimensional 1H, 29Si and 27Al NMR study

    19th General Meeting of the International Mineralogical Association (IMA),  2006年 

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  • Cation order and hydrogen bonding of d-AlOOH, phase egg and aluminous stishovite: An NMR and Raman study

    19th General Meeting of the International Mineralogical Association (IMA),  2006年 

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  • topaz-OH(Al2SiO4(OH)2)の高圧相:構造とNMR/Raman 分光による特徴

    日本地球惑星科学連合2006年大会  2006年 

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  • High-pressure form of topaz-OH: Structure and characterization by NMR and Raman

    19th General Meeting of the International Mineralogical Association (IMA),  2006年 

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  • 第一原理EFG計算とNMRへの応用

    日本鉱物学会年会  2005年 

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  • 29Si and 27Al NMR characteristics of octahedral Si-Al disorder in high-pressure aluminosilicate minerals

    第44回NMR討論会-第1回アジア太平洋NMRシンポジウム合同会議,  2005年 

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  • Al2O3-SiO2-H2O 系高圧相のカチオン秩序及び水素結合

    日本鉱物学会年会  2005年 

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  • ナトリウムケイ酸塩メルトに対するいくつかの硫黄溶解機構;ラマンおよび29Si MAS NMR分光法

    地球惑星科学関連学会2004年合同大会  2004年 

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  • Energetics, and vibrational and NMR characteristics of possible sulfur species in silicate melts: An ab initio calculation

    地球惑星科学関連学会2004年合同大会  2004年 

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  • STABILITY AND NMR CHARACTERISTICS OF POSSIBLE SULUR SPECIES IN SILICATE MELTS AND GLASSES: AN AB INITIO CALCULATION

    XX International Congress on Glass  2004年 

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  • The dissolution mechanism of water in alkaline earth silicate and aluminosilicate melts: One view from 1H MAS NMR

    地球惑星科学関連学会2004年合同大会  2004年 

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  • Mg2SiO4リングウッダイト及びワーズレアイトに関する予備的29Si MAS NMR研究

    地球惑星科学関連学会2003年合同大会  2003年 

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  • Effect of sulfate sulfur on structure of Na2O-SiO2 glasses; 29Si MAS NMR, Raman and FT-IR studies

    13th Annual V.M. Goldschmidt Conference,  2003年 

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  • 含硫酸アルカリ珪酸塩ガラスの珪酸塩陰イオン(Qn種)分布:ラマンおよび29Si MAS NMR

    地球惑星科学関連学会2003年合同大会  2003年 

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  • The dissolution mechanism of water in alkaline earth silicate and aluminosilicate melts: One view from 1H MAS NMR

    13th Annual V.M. Goldschmidt Conference,  2003年 

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  • 29Si及び1H MAS NMRから見たケイ酸塩メルトにおける水の溶解機構の組成依存性

    地球惑星科学関連学会2002年合同大会  2002年 

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  • NMR evidence for a new water dissolution mechanism in alkaline earth silicate melts

    12th Annual V.M. Goldschmidt Conference  2002年 

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  • NMR分光法によるイオウを含むNa2O-SiO2系ガラスのネットワーク縮重合

    地球惑星科学関連学会2002年合同大会  2002年 

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  • The dissolution mechanisms of forsterite and enstatite: Constraints from 29SI and 1H MAS NMR

    12th Annual V.M. Goldschmidt Conference  2002年 

     詳細を見る

  • Mg2SiO4フォルステライトの溶解機構: 29Si及び1H MAS NMRによる制約

    地球惑星科学関連学会2002年合同大会  2002年 

     詳細を見る

  • 非経験的分子軌道法による含水珪酸塩中のOH基のO-17, H-1,及びH-2 NMRパラメータの計算

    地球惑星科学関連学会2001年合同大会  2001年 

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  • The effect of sulfur on silicate network structure in sodium silicate glasses

    International Symposium, Transport of Materials in the Dynamic Earth  2001年 

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  • Ab Initio Calculation of the 17O and 1H NMR Parameters for Various OH Groups in Hydrous Silicates

    International Symposium, Transport of Materials in the Dynamic Earth  2001年 

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  • NMR Evidence for a New Water Dissolution Mechanism in Depolymerized Silicate Melts: Results for Hydrous Diopside Composition

    International Symposium, Transport of Materials in the Dynamic Earth  2001年 

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  • 縮重度の低いケイ酸塩メルトにおける水の新しい溶解機構 含水ダイオプサイドガラスのNMR結果

    地球惑星科学関連学会2001年合同大会  2001年 

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  • 非経験的分子軌道法計算によるシリコン,酸素NMRパラメータの予測

    地球惑星科学関連学会2000年合同大会  2000年 

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  • 含水珪酸塩ガラス中のOH基のNMR特徴:非経験的分子軌道法計算

    地球惑星科学関連学会2000年合同大会  2000年 

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