High-pressure polymorphs of LiPN2： A first-principles study  

作　　者：Jian Lv Xin Yang Dan Xu Yu-Xin Huang Hong-Bo Wang Hui Wang 

机构地区：[1]College of Materials Science and Engineering, Jilin University, Changchun 130012, China [2]State Key Lab of Superhard Materials, College of Physics, Jilin University, Changchun 130012, China [3]College of Basic Science, Changchun University of Technology, Changchun 130012, China

出　　处：《Frontiers of physics》2018年第5期147-152,共6页物理学前沿（英文版）

基　　金：The authors acknowledge funding support from the National Natural Science Foundation of China （GrantNos. 11474128 and 11534003）, Science Challenge Project （Grant No. TZ2016001）, National Key Research and Development Pro- gram of China （Grant Nos. 2016YFB0201200, 2016YFB0201201, and 2016YFB0201204）, and Program for JLU Science and Tech- nology Innovative Research Team. Parts of the calculations were performed in the high-performance computing center of Jilin Uni- versity.

摘　　要：In this work, high-pressure phase behavior of LiPN2 within 0-300 GPa was studied by using an unbiased structure searching method in combination with first-principles calculations. Three pressure- induced phase transitions were predicted, as tI16 →hR4 →cF64 → oP8 at 44, 136, and 259 GPa, respectively. The six-fold coordination environments were found for all high-pressure polymorphs, which are substantially different from the four-fold coordination environments observed in the tI16 structure. The hR4 and cF64 structures consist of close-packed PN6 and LiN6 octahedra connected by edge-sharing, whereas the oP8 structure is built up from edge- and face-sharing PN6 and LiN6 octahedra with N lying in the center of the trigonal prisms. The electronic structure analysis reveals that LiPN2 is a semiconductor within the pressure range studied and P-N and Li-N bonds are covalent and ionic, respectively. The results obtained are expected to provide insight and guidance for future experiments on LiPN2 and other alkali metal nitridophosphates.In this work, high-pressure phase behavior of LiPN2 within 0-300 GPa was studied by using an unbiased structure searching method in combination with first-principles calculations. Three pressure- induced phase transitions were predicted, as tI16 →hR4 →cF64 → oP8 at 44, 136, and 259 GPa, respectively. The six-fold coordination environments were found for all high-pressure polymorphs, which are substantially different from the four-fold coordination environments observed in the tI16 structure. The hR4 and cF64 structures consist of close-packed PN6 and LiN6 octahedra connected by edge-sharing, whereas the oP8 structure is built up from edge- and face-sharing PN6 and LiN6 octahedra with N lying in the center of the trigonal prisms. The electronic structure analysis reveals that LiPN2 is a semiconductor within the pressure range studied and P-N and Li-N bonds are covalent and ionic, respectively. The results obtained are expected to provide insight and guidance for future experiments on LiPN2 and other alkali metal nitridophosphates.

关 键 词：lithium nitridophosphates phase transition high pressure first principles 

分 类 号：TP18[自动化与计算机技术—控制理论与控制工程] TP319[自动化与计算机技术—控制科学与工程]