Crystal structure prediction based on first-principles calculations is often achieved by applying relaxation to randomly generated initial structures. Relaxing a structure requires multiple optimization steps. It is time consuming to fully relax all the initial structures, but it is difficult to figure out which initial structure leads to the optimal solution in advance. In this paper, we propose a optimization method for crystal structure prediction, called Look Ahead based on Quadratic Approximation, that optimally assigns optimization steps to each candidate structure. It allows us to identify the most stable structure with a minimum number of total local optimization steps. Our simulations using known systems Si, NaCl, Y₂Co₁₇, Al₂O₃, and GaAs showed that the computational cost can be reduced significantly compared to random search. This method can be applied for controlling all kinds of local optimizations based on first-principles calculations to obtain best results under restricted computational resources.

基于第一性原理计算的晶体结构预测通常是通过将松弛应用于随机生成的初始结构来实现的。放宽结构需要多个优化步骤。完全放松所有初始结构是很费时的，但是很难预先弄清楚哪种初始结构会导致最佳解决方案。在本文中，我们提出了一种用于晶体结构预测的优化方法，称为基于二次逼近的超前查找（Look Ahead），该方法可以为每个候选结构最佳地分配优化步骤。它使我们能够以最少的总局部优化步骤来确定最稳定的结构。我们使用已知系统Si，NaCl，Y ₂ Co ₁₇，Al ₂ O _3进行的模拟和GaAs表明，与随机搜索相比，计算成本可以大大降低。该方法可用于基于第一性原理计算的各种局部优化控制，以在有限的计算资源下获得最佳结果。