Local-environment fluctuations and densities of states in substitutionally disordered alloys
Local-environment fluctuations and densities of states in substitutionally disordered alloys
复制标题
替代无序合金中的局部环境波动和态密度
DOI：
10.1103/physrevb.29.555
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发表时间：
1984
影响因子：
3.7
通讯作者：
H. Winter
中科院分区：
文献类型：
--
作者：
A. Gonis;G. M. Stocks;W. Butler;H. Winter
我们报告的状态密度（DOS）的计算与特定的原子配置的紧凑的集群在替代无序合金描述的哈密顿与非重叠的松饼-锡势。计算的方法包括在评估的绿色功能与嵌入在一个等效不变的有效介质，如确定的Korringa-Kohn-Rostoker，相干势近似（KKR-CPA）方法中的原子簇。这种方法产生定义明确的，分析的，物理上有意义的结果，并适当考虑晶格的晶体结构。数值结果报告的近邻集团在一维模型muffin-tin合金，以及在现实的${\mathrm{Ag}}_{c}{\mathrm{Pd}}_{1\ensuremath{-}c}$合金。与许多集群配置相关的DOS表现出更多的结构比单站点KKR-CPA方法中计算的DOS，这可以理解的基本物理量，如合金成分的相对散射强度，和晶格的对称性。讨论了团簇态密度在计算替位无序合金物理性质中的几种可能的应用。
We report calculations of densities of states (DOS) associated with specific atomic configurations of compact clusters in substitutionally disordered alloys describable by a Hamiltonian with nonoverlapping muffin-tin potentials. The method of calculation consists in evaluating the Green function associated with a cluster of atoms embedded in a translationally invariant effective medium such as the one determined in the Korringa-Kohn-Rostoker, coherent-potential-approximation (KKR-CPA) method. This method yields well-defined, analytic, and physically meaningful results and takes proper account of the crystal structure of the lattice. Numerical results are reported for near-neighbor clusters in both one-dimensional model muffin-tin alloys, as well as in realistic ${\mathrm{Ag}}_{c}{\mathrm{Pd}}_{1\ensuremath{-}c}$ alloys. The DOS associated with many cluster configurations exhibit more structure than the DOS calculated in the single-site KKR-CPA method, which can be understood in terms of fundamental physical quantities, such as the relative scattering strength of the alloy constituents, and of the symmetry of the lattice. Several possible applications of cluster DOS in calculating the physical properties of substitutionally disordered alloys are discussed.