Structural modeling of transition-metal-metalloid glasses by use of tight-binding-bond forces.
Structural modeling of transition-metal-metalloid glasses by use of tight-binding-bond forces.
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DOI：
10.1103/physrevb.47.5689
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发表时间：
1993-03
期刊：
影响因子：
--
通讯作者：
Hausleitner;Hafner
中科院分区：
文献类型：
--
作者：
Hausleitner;Hafner
一种最近发展的用于计算无序材料中原子间力的紧束缚键方法被扩展到非晶态过渡金属 - 类金属合金。结果表明，过渡金属d电子与类金属p电子的相互作用导致了强共价键合力，这反映在成对相互作用的显著非加和性上。非晶态合金的结构通过模拟分子动力学淬火来建模。Fe - B、Ni - B、Fe - P和Ni - P玻璃的结果与衍射实验非常吻合。结果表明，共价键合力导致了一种化学和拓扑序，类似于在基于三角棱柱单元堆积的立体化学定义模型中所假定的那样。分子动力学模拟还预测了一种中程有序（在15 - 20埃尺度上的浓度涨落），这与现有的小角散射数据一致。
A recently developed tight-binding-bond approach for the calculation of interatomic forces in disordered materials is extended to amorphous transition-metal--metalloid alloys. It is shown that the interaction of the transition-metal d electrons with the metalloid p electrons leads to strong covalent bonding forces that are reflected in a pronounced nonadditivity of the pair interactions. The structure of the amorphous alloys is modeled by a simulated molecular-dynamics quench. Results for Fe-B, Ni-B, Fe-P, and Ni-P glasses are in good agreement with diffraction experiments. It is shown that the covalent bonding forces lead to a chemical and topological order similar to that postulated in stereochemically defined models based on the packing of trigonal prismatic units. The molecular-dynamics simulations also predict a medium-range order (concentration fluctuations on a scale of 15--20 \AA{}) in agreement with the existing small-angle scattering data.