Modulated Electron Density of Inorganic Compounds using SR

使用 SR 调制无机化合物的电子密度

基本信息

批准号：
08044132
负责人：
ISHIZAWA Nobuo
金额：
$ 2.56万
依托单位：
Tokyo Institute of Technology
依托单位国家：
日本
项目类别：
Grant-in-Aid for international Scientific Research
财政年份：
1996
资助国家：
日本
起止时间：
1996 至 1997
项目状态：
已结题

项目摘要

The present study has been carried out with the objective to determine modulated structures and electron densities of functional inorganic materials using synchrotron radiations. The precise analysis using the single crystal diffraction technique has so far been suffered from the extinction effect which often reduces the incident intensity expected from the kinematical theory. The present study seems to have succeeded in eliminating the problem from practical point of view, by the use of small crystal of about 10 micrometer in size and by the use of the synchrotron source with high flux. The results obtained are (a) determination of incommensurately modulated structure in the Ta_2O_5-WO_3, solid solution, (b) determination of the structure of Mg_6SO_2(OH)_<14> needle-shaped tiny crystals which can not be grown more than 100 micron in length and several micron in width, (c) electron density measurements on SmFeO_3, YFeO_3, HoFeO_3, C-type rare-earth sesquioxides, Y_2BaCuO_5 superconduction-related compound, LaOCl layred-type structure, LiNbO_3 and LiTaO_3 optoelectronic materials, a synthetic mineral of ferrian aluminian diopside, cobalt-containing olivine, (d) determination of compositely modulated structure of Nb_2Zr_<X-2>O_<2X-1> with x=8, (e) development of a fast X-ray counter using the avalanche-photo-diodes, etc. All these studies were done at the Photon Factory, High-Energy Physics Laboratory (KEK), Japan, in most cases, using the horizontal-type four-circle diffractometer at the beamline 14A.The head investigator now bears in mind a thought that this project has successfully conducted by the group members and the results have contributed to the scientific communities involved in the materials science and crystallography to a great extent.

本研究的目的是为了确定使用同步加速器辐射确定功能无机材料的调制结构和电子密度。迄今为止，使用单晶衍射技术进行的精确分析已经遭受了灭绝效应，这通常会降低运动学理论所期望的入射强度。从实际的角度，通过使用约10微米的小晶体和使用具有高通量的同步子源，本研究似乎已经成功地消除了问题。获得的结果是（a）确定在TA_2O_5-WO_3中确定不稳定的调制结构，固体解决方案，（b）确定MG_6SO_2（OH）_ <14>针状的微晶的结构，该晶体无法在宽度上长度不超过100 micron，（c）wifth，（c）y vie_3，y 33，y fifeo_3，y fifeo_3，yfeo_3，y fifeo_3，yfeo3，yfeo3，yfie3，yfeo3，yfeo3，yfie3，yfeo3，yfeo3，3 C型稀有盐酸替代剂，Y_2BACUO_5与超模拟相关化合物，LAOCL Layred-type结构，Linbo_3和Litao_3光电材料，Ferrian Aluminian Diopside的合成矿物质，辅助olivine Olivine（D）的结构（D） NB_2ZR_ <x-2> O_ <2x-1>使用X = 8，（e）使用雪崩 - 光电二极管等快速X射线计数等。所有这些研究均在光子厂，高能物理实验室（KEK），日本，在大多数情况下，在大多数情况下，使用水平型四范围的范围，这是在公平范围内进行的。小组成员成功地进行了项目，结果在很大程度上为参与材料科学和晶体学的科学社区做出了贡献。