Ti XAS of a novel Cs-Ti silicate
Ti XAS of a novel Cs-Ti silicate
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新型 Cs-Ti 硅酸盐的 Ti XAS
DOI：
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发表时间：
1997
期刊：
影响因子：
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通讯作者：
S. Conradson
中科院分区：
文献类型：
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作者：
N. Hess;M. Balmer;B. Bunker;S. Conradson
用XANES和EXAFS测定了几种已知结构的氧化钛标准物和两种未知CsTiSi{sub 2}O{sub 6.5}成分的氧化钛标准物中钛的配位环境，一种是无定形的，一种是完全结晶的。对未知分子的XANES和EXAFS数据分析表明，Ti{sup 4+}在CsTiSiO{sub 2}O{sub 6.5}中为5倍坐标，位点高度扭曲。Ti预边缘特征的强度与能量的关系图导致6倍、5倍和4倍坐标Ti被分离成三个不同的区域。EXAFS和XANES数据表明，非晶和结晶CsTiSi{sub 2}O{sub 6.5}样品的Ti配位环境相同，表明Ti配位环境在结晶过程中较早形成。在相同样品上的初步测量表明，非晶CsTiSi{sub 2}O{sub 6.5}样品的Cs配位环境不同，表明Cs配位环境在结晶过程中形成较晚。
Ti XANES and EXAFS were performed to determine the coordination environment of Ti in several Ti oxide standards with known structures and two unknowns with CsTiSi{sub 2}O{sub 6.5} composition, one amorphous and one fully crystalline. Analysis of both the XANES and EXAFS data of the unknowns indicate that Ti{sup 4+} is 5-fold coordinate in CsTiSiO{sub 2}O{sub 6.5} and that the site is highly distorted. Plots of intensity versus the energy of a Ti pre-edge feature result in the separation of 6-, 5-, and 4-fold coordinate Ti into three distinct regions. EXAFS and XANES data show that the Ti coordination environment for the amorphous and crystalline CsTiSi{sub 2}O{sub 6.5} samples is the same indicating that the Ti coordination environment forms early in the crystallization process. Preliminary measurements at the Cs K-edge EXAFS on the same samples shows that the Cs coordination environment is different for the amorphous and the crystalline CsTiSi{sub 2}O{sub 6.5} samples suggesting that the Cs coordination environment forms late in the crystallization process.