Quantum Statistical Approach to Debye-Waller Factor in EXAFS, EELS and ARXPS. II. Application to One-Dimensional Models
Quantum Statistical Approach to Debye-Waller Factor in EXAFS, EELS and ARXPS. II. Application to One-Dimensional Models
复制标题
EXAFS、EELS 和 ARXPS 中德拜-沃勒因子的量子统计方法。
DOI：
10.1143/jpsj.63.1036
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发表时间：
1994
影响因子：
1.7
通讯作者：
T. Fujikawa
中科院分区：
文献类型：
--
作者：
T. Miyanaga;T. Fujikawa
本文用第一性原理量子统计方法计算了一维模型的EXAFS、EELS和ARXPS中Debye-Waller因子随温度的变化。与晶体的衍射Debye-Waller因子相比，我们不必担心一维和二维声子系统中这些热因子的发散。我们考虑非简谐莫尔斯势作为最近邻相互作用。我们考虑到四次项，并估计四阶累积量的单原子和双原子链在宽的温度范围从低温量子效应是重要的，高温中的经典近似工程。在双原子模型链中讨论了光学和声学模贡献的特征。这里得到的结果给我们提供了这些热因素的明确的物理见解。
Temperature dependence of Debye-Waller factor in EXAFS, EELS and ARXPS is calculated for one-dimensional models on the basis of first principle quantum statistical method developed in the previous paper I. In contrast to diffraction Debye-Waller factors for crystal we have no need to worry about the divergence for these thermal factors in one- and two-dimensional phonon systems. We consider anharmonic Morse potential as nearest neighbor interaction. We take up to quartic term into account and estimate up to fourth order cumulants for both monatomic and diatomic chains in wide temperature range from low temperature in which quantum effect is important, to high temperature in which classical approximation works. Characteristic features of the contributions from optical and acoustic modes are discussed in the diatomic model chain. The result obtained here give us clear physical insights of those thermal factors.