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 tim...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,Y_(2)Co_(17),Al_(2)O_(3),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.展开更多
基金This work was supported by the‘Materials research by Information Integration’Initiative(MI2I)project and Core Research for Evolutional Science and Technology(CREST)[Grant number JPMJCR1502]from Japan Science and Technology Agency(JST).It was also supported by Grant-in-Aid for Scientific Research on Innovative Areas“Nano Informatics”[Grant number 25106005]from the Japan Society for the Promotion of Science(JSPS).
文摘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,Y_(2)Co_(17),Al_(2)O_(3),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.
