Coupling of temperature with pressure induced initial decomposition mechanisms of two molecular crystals: An ab initio molecular dynamics study

Journal of Chemical Sciences

DONG XIANG¹  GUOLIN XIONG¹  WEIHUA ZHU1¹  QIONG WU1¹  HEMING XIAO¹ 

[1] Institute for Computation in Molecular and Materials Science and Department of Chemistry, School of Chemical Engineering, Nanjing University of Science and Technology, Nanjing 210094, China$$

关键词: Ab initio molecular dynamics;    Pentaerythritol tetranitrate;    5-Nitro-2;    4-dihydro-1;    2;    4-triazole-3- one;    Initiation decomposition mechanism;    high temperature;    high pressure;   

DOI  :  

来源: Indian Academy of Sciences

【 摘 要 】

Ab initio molecular dynamics simulations were performed to study the initiation of decompositionand formation of first products of two molecular crystals pentaerythritol tetranitrate (PETN) and 5-nitro-2,4-dihydro-1,2,4-triazole-3-one (NTO) under thermal decomposition temperature (475 K for PETN and 531 Kfor NTO) coupled with different pressures (1-5 GPa). The pressure effects on the initial decomposition stepsand initially generated products on PETN and NTO were very different. PETN was triggered by C-H... O intermolecular hydrogen transfer. The initial decomposition mechanism was independent of the pressure. ForNTO, two different initial decomposition mechanisms were found. At 1, 2, and 3 GPa, it was triggered by NH....O intermolecular hydrogen transfer, while at 4 and 5 GPa, it was triggered by N-H.....N intermolecularhydrogen transfer. This indicates that the initial decomposition mechanism was dependent on the pressure.Our study may provide new insights into initial mechanisms and decomposition reactions of molecular crystalexplosives under thermal decomposition temperature coupled with different pressures with details at atomiclevel.

【 授权许可】

Unknown