Determining metal ion distributions using resonant scattering at very high-energy K-edges:Bi/Pb in Pb5Bi6Se14
Determining metal ion distributions using resonant scattering at very high-energy K-edges:Bi/Pb in Pb5Bi6Se14
复制标题
使用极高能量 K 边的共振散射确定金属离子分布：Pb5Bi6Se14 中的 Bi/Pb
DOI：
10.1107/s0021889805005686
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发表时间：
2005
影响因子：
6.1
通讯作者：
M. Kanatzidis
中科院分区：
文献类型：
--
作者：
Yuegang Zhang;A. Wilkinson;P. Lee;S. Shastri;D. Shu;D. Chung;M. Kanatzidis
利用先进光子源同步辐射的成像板探测器在~ 86 keV下收集的Pb和Bi k边缘下方的粉末衍射数据，用于检测Pb 5 Bi 6 Se 14[空间群P2 1 /m， a = 16.0096 (2) a, b = 4.20148 (4) a, c= 21.5689 (3) a和β = 97.537(1)°]中11个不同晶体位置上的Pb/Bi分布。利用吸收光谱的Kramers-Kronig变换和参考化合物的衍射图分析确定了分析所需的散射因子。即使在k边缘有相对较低的散射对比度，也可以确定Pb/Bi的分布并探测材料中阳离子位空位的存在。目前的结果表明，当来自样品或样品环境/容器的吸收是获取低能量边缘高质量谐振散射数据的主要障碍时，高能k边缘的谐振散射测量是一种可行的，也许是更可取的途径。
Powder diffraction data collected at ∼86 keV, and just below both the Pb and the Bi K-edges, on an imaging plate detector using synchrotron radiation from the Advanced Photon Source have been used to examine the Pb/Bi distribution over the 11 crystallographically distinct sites in Pb 5 Bi 6 Se 14 [space group P2 1 /m, a = 16.0096 (2) A, b = 4.20148 (4) A, c= 21.5689 (3) A and β = 97.537 (1)°]. The scattering factors needed for the analyses were determined both by Kramers-Kronig transformation of absorption spectra and by analyses of diffraction patterns from reference compounds. Even with the relatively low scattering contrast that is available at the K-edges, it was possible to determine the Pb/Bi distribution and probe the presence of cation site vacancies in the material. The current results indicate that resonant scattering measurements at high-energy K-edges are a viable, and perhaps preferable, route to site occupancies when absorption from the sample or sample environment/container is a major barrier to the acquisition of high-quality resonant scattering data at lower-energy edges.