High-energy-density metal nitrides with armchair chains  

作　　者：Jianan Yuan Kang Xia Chi Ding Xiaomeng Wang Qing Lu Jian Sun 

机构地区：[1]National Laboratory of Solid State Microstructures,School of Physics and Collaborative Innovation Center of Advanced Microstructures,Nanjing University,Nanjing 210093,People’s Republic of China [2]Department of Applied Physics,College of Science,Nanjing Forestry University,Nanjing 210037,China

出　　处：《Matter and Radiation at Extremes》2022年第3期47-53,共7页极端条件下的物质与辐射（英文）

基　　金：J.S.gratefully acknowledges financial support from the National Natural Science Foundation of China(Grant Nos.12125404,11974162,and 11834006);the Fundamental Research Funds for the Central Universities.K.X.acknowledges support from the National Natural Science Foundation of China under Grant No.12004185;the Natural Science Foundation of the Jiangsu Higher Education Institutions of China under Grant No.20KJB140016;the Scientific Research Start-up Funds of Nanjing Forestry University(No.163101110);the China Postdoctoral Science Foundation(Grant No.2019M651767).

摘　　要：Polymeric nitrogen has attracted much attention owing to its possible application as an environmentally safe high-energy-density material.Based on a crystal structure search method accelerated by the use of machine learning and graph theory and on first-principles calculations,we predict a series of metal nitrides with chain-like polynitrogen(P_(21)-AlN_(6),P2_(1)-GaN_(6),P-1-YN_(6),and P_(4)/mnc-TiN_(8)),all of which are estimated to be energetically stable below 40.8 GPa.Phonon calculations and ab initio molecular dynamics simulations at finite temperature suggest that these nitrides are dynamically stable.We find that the nitrogen in these metal nitrides can polymerize into two types of poly-N^(2-)_(4)chains,in which theπelectrons are either extended or localized.Owing to the presence of the polymerized N4 chains,these metal nitrides can store a large amount of chemical energy,which is estimated to range from 4.50 to 2.71 kJ/g.Moreover,these compounds have high detonation pressures and detonation velocities,exceeding those of conventional explosives such as TNT and HMX.

关 键 词：CHAINS MATERIAL ENERGY 

分 类 号：TG14[一般工业技术—材料科学与工程]