Properties and Phase Transitions of the Solid $\beta$-HMX: Different Force Fields

Authors

  • Shuo Liu College of Life Science and Biotechnology, Shanghai Jiaotong University, Shanghai 200240, China
  • Jing Chang College of Life Science and Biotechnology, Shanghai Jiaotong University, Shanghai 200240, China
  • Dong-Qing Wei College of Life Science and Biotechnology and Research Center Astronautics, Shanghai Jiaotong University, Shanghai 200240, China
  • Xiang-Rong Chen College of Physical Science and Technology, Sichuan University, Chengdu 610064, China
  • Qing-Ming Zhang State Key Laboratory of Explosion Science and Technology, Beijing Institute of Technology, Beijing 100081, China
  • Zi-Zheng Gong National Key Laboratory of Science and Technology on Reliability and Environment Engineering, Beijing Institute of Spacecraft Environment Engineering, Beijing 100094, China
  • Guang-Fu Ji Laboratory for Shock Wave and Detonation Physics Research, Institute of Fluid Physics, Chinese Academy of Engineering Physics, Mianyang 621900, China
  • Yong-Xin Guo Department of Physics, Liaoning University, Shenyang, Liaoning 110036, China

DOI:

https://doi.org/10.4208/jams.032811.051411a

Keywords:

$\beta$-HMX crystal, molecular dynamics, force fields, phase transitions.

Abstract

The structure, cell volume and lattice constants of $β$-octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine ($β$-HMX) crystal are studied by using the classical molecular dynamics method. The variations of cell volume and lattice constants are presented and discussed under different pressures and temperatures. The main purpose of the present work is to understand effect of different force fields, the CVFF and PCFF force fields were used instead of usual COMPASS. It is found that the cell volume is less satisfactory, and there was an abrupt change at 370 K and 440 K for the lattice constants and cell volume with CVFF force field. However, for PCFF force field, an abrupt change occurred at 360 K and 430 K, respectively. It means that $β$-HMX may have phase transitions at these temperatures in accordance with experimental observation. It is suggested that selection of suitable force field play an important role in achieving desired accuracy of simulation results.

Published

2012-03-01

Issue

Section

Articles