Crystal structure optimisation using an auxiliary equation of state.
Crystal structure optimisation using an auxiliary equation of state.
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使用辅助状态方程优化晶体结构。
DOI：
10.1063/1.4934716
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发表时间：
2015
期刊：
影响因子：
--
通讯作者：
A. Walsh
中科院分区：
文献类型：
--
作者：
A. Jackson;J. Skelton;Christopher H. Hendon;K. Butler;A. Walsh
局部晶体结构优化的标准程序涉及大量的能量和力计算。通常计算能量-体积曲线，拟合平衡单元体积周围的状态方程。这是一个计算密集的过程，特别是对于低对称性晶体结构，其中每个等容优化涉及许多自由度上的能量最小化。这样的程序可能是禁止的非本地交换相关泛函或其他“超越”密度泛函理论电子结构技术，特别是在分析梯度不可用。我们提出了一个简单的方法，有效的优化晶体结构的基础上一个已知的状态方程。平衡体积可以从一个单点计算中预测，如果需要，可以通过连续计算进行改进。该方法被验证为PbS，PbTe，ZnS，和ZnTe使用9个密度泛函和应用到四元半导体Cu 2 ZnSnS 4和磁性金属有机框架HKUST-1。
Standard procedures for local crystal-structure optimisation involve numerous energy and force calculations. It is common to calculate an energy-volume curve, fitting an equation of state around the equilibrium cell volume. This is a computationally intensive process, in particular, for low-symmetry crystal structures where each isochoric optimisation involves energy minimisation over many degrees of freedom. Such procedures can be prohibitive for non-local exchange-correlation functionals or other "beyond" density functional theory electronic structure techniques, particularly where analytical gradients are not available. We present a simple approach for efficient optimisation of crystal structures based on a known equation of state. The equilibrium volume can be predicted from one single-point calculation and refined with successive calculations if required. The approach is validated for PbS, PbTe, ZnS, and ZnTe using nine density functionals and applied to the quaternary semiconductor Cu2ZnSnS4 and the magnetic metal-organic framework HKUST-1.