高压下LiSi_7结构的第一性原理研究

Crystal Structure of LiSi_7 under High Pressure: Ab Initio Calculations

应用基于粒子群优化算法的卡里普索(CALYPSO)晶体结构预测方法,从理论上系统的研究了0～50 GPa压力下富硅的锂硅化合物LiSi_7,发现了一种新型的四方结构,其空间群为I4/mmm。利用基于密度泛函理论的第一性原理计算方法,对它的晶体结构、动力学稳定性、电子结构以及力学稳定性进行了系统地研究。本工作为高压下富硅锂硅化合物的合成起到了一定的指导作用。

Based on the swarm-intelligence structural prediction method,we studied the silicon-rich LiSi 7 compound during the pressure range of 0~50 GPa,and found a novel tetragonal phase with the space group of I4/mmm .The crystal structure,dynamical stability,electronic structure,and mechanical stability were systematically performed via first principles calculations.Our work may provide insights for the synthesis of high-pressure rich-silicon lithium silicide compounds.