Neutron and X-ray total scattering study of hydrogen disorder in fully hydrated hydrogrossular, Ca3Al2(O4H4)3
Neutron and X-ray total scattering study of hydrogen disorder in fully hydrated hydrogrossular, Ca3Al2(O4H4)3
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DOI：
10.1007/s00269-017-0923-0
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发表时间：
2018-04
影响因子：
1.4
通讯作者：
D. Keen;D. Keeble;T. Bennett
中科院分区：
文献类型：
--
作者：
D. Keen;D. Keeble;T. Bennett
完全水合的钙铝榴石或卡托石的结构在每个 O4 四面体中包含四个 O-H 键的不寻常排列。测量了粉末状氘化样品的中子和 X 射线总散射，以研究该 O4D4 团簇的局部排列。直接从配对分布函数确定的 O-D 键长为 0.954 Å，尽管平均 O 和 D 位置之间的 Rietveld 精修距离略小。超晶胞模型对总散射数据的逆蒙特卡罗细化表明，除了正确确定的 O-D 键长的结果之外，几乎没有迹象表明 O4D4 结构与仅由布拉格衍射确定的平均结构所预期的结构存在局部显着差异。
The structure of fully hydrated grossular, or katoite, contains an unusual arrangement of four O–H bonds within each O4tetrahedra. Neutron and X-ray total scattering from a powdered deuterated sample have been measured to investigate the local arrangement of this O4D4cluster. The O–D bond length determined directly from the pair distribution function is 0.954 Å, although the Rietveld-refined distance between average O and D positions was slightly smaller. Reverse Monte Carlo refinement of supercell models to the total scattering data show that other than the consequences of this correctly determined O–D bond length, there is little to suggest that the O4D4structure is locally significantly different from that expected based on the average structure determined solely from Bragg diffraction.