Multiple-edge EXAFS refinement: Short-range structure in liquid and crystalline Sn
Multiple-edge EXAFS refinement: Short-range structure in liquid and crystalline Sn
复制标题
DOI：
10.1103/physrevb.53.6174
复制
发表时间：
1996-03
影响因子：
3.7
通讯作者：
A. Cicco
中科院分区：
文献类型：
--
作者：
A. Cicco
L边扩展X射线吸收精细结构~EXAFS！用同步辐射收集了固态和液态锡的光谱。局部结构上的信息已获得通过同时分析Sn L3，L2和L1-边EXAFS光谱通过使用原始的数据分析方案的基础上从头多次散射GNXAS方法。使用的三个边缘允许扩展的能量范围内的有用的数据，增加了所得到的结构参数的准确性。提供了多边缘数据分析方法的细节。讨论了该方法用于单原子和多原子系统多边结构研究的一般意义。一个非常好的协议与衍射数据被发现结晶锡。第一近邻分布作为温度的函数进行了研究。提供了结构参数的统计误差。通过X射线衍射数据获得的模型对分布函数g（r）在T5245 °C的液态Sn中被细化。EXAFS结构信号对短期相关性非常敏感。发现g（r）的第一个峰的底部更陡，平均距离比前面指出的稍短。由于EXAFS数据中的随机误差，g（r）上的误差条也被显示出来。分配给短程共价四面体配置的三体信号的签名是证明。
L-edge extended x-ray-absorption fine structure ~EXAFS! spectra of solid and liquid tin have been collected by using synchrotron radiation. Information on local structure has been obtained by simultaneous analysis of Sn L3, L2, and L1-edge EXAFS spectra by using an original data-analysis scheme based on the ab initio multiple-scattering GNXAS method. The use of the three edges allowed the extension of the energy range of the useful data increasing the accuracy of the derived structural parameters. Details of the multiple-edge data-analysis methodology are provided. The general interest of the method for multiple-edge structural studies of monatomic and multiatomic systems is discussed. A very good agreement with diffraction data is found for crystalline Sn. The first-neighbor distribution is studied as a function of temperature. Statistical errors on the structural parameters are provided. The model pair distribution function g(r) obtained by x-ray-diffraction data is refined in liquid Sn at T5245 °C. The EXAFS structural signal is shown to be very sensitive to the short-range correlations. The foot of the first peak of the g(r) is found to be steeper and the mean distance is found slightly shorter than previously indicated. Error bars on the g(r), due to random errors in the EXAFS data, are also shown. The signature of a three-body signal assigned to short-range covalent tetrahedral configurations is evidenced.