The crystal chemistry of julgoldite-Fe3+ from Bombay, India, studied using synchrotron X-ray powder diffraction and 57Fe Mössbauer spectroscopy
The crystal chemistry of julgoldite-Fe3+ from Bombay, India, studied using synchrotron X-ray powder diffraction and 57Fe Mössbauer spectroscopy
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使用同步加速器 X 射线粉末衍射和 57Fe 穆斯堡尔光谱研究产自印度孟买的金金矿-Fe3+ 的晶体化学
DOI：
10.2138/am-2003-0717
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发表时间：
2003
影响因子：
3.1
通讯作者：
M. Dapiaggi
中科院分区：
文献类型：
--
作者：
Gilberto Artioli;Charles A. Geiger;M. Dapiaggi
摘要通过57FEMössbauer光谱研究了来自印度孟买的Julgoldite-Fe3+的晶体结构，并且在Mössbauer测量中仅检测到铁铁，并且在两个不同的八个不同的位置中都检测到了铁铁。 80。根据Rietveld的改进，Fe3+阳离子位于X和Y-o-o-o-o-o-o-o-o-o-o-octeDral位置，原子百分比约为25％和75％的孟买Julgoldite样品的化学公式为CA8（Fe3+2.7Al1.1mg0.2）（FE3+8.0）SI12O42（OH）14通过简单的晶体化学考虑，这种分析不能为泵素型米拉群中的混合价阳离子及其晶体内分配行为提供定量结果Mössbauer抽象双打和Fe-Intracrystalline分配行为的分析参考了以前的不同泵素型矿物质的作品。
Abstract The crystal structure of julgoldite-Fe3+ from Bombay, India, was investigated by 57Fe Mössbauer spectroscopy and synchrotron X-ray powder diffraction. Only ferric iron was detected in the Mössbauer measurements and it occurs at two different octahedral sites in the atomic ratio 20:80. Based on Rietveld refinements, the Fe3+ cations are located at the X- and Y-octahedral sites with atomic percentages of about 25% and 75%, respectively. The resulting chemical formula of the Bombay julgoldite sample is Ca8(Fe3+2.7Al1.1Mg0.2)(Fe3+8.0)Si12O42(OH)14. The oxidation state of Fe is not the same as that arrived at through simple crystal-chemical considerations. Such analysis cannot give quantitative results for the valence state of mixed-valence cations in pumpellyite-type minerals and their intracrystalline partitioning behavior. Assignments of the Mössbauer absorption doublets and an analysis of Fe-intracrystalline partitioning behavior are discussed with reference to previous works on different pumpellyite-type minerals.