Pressure effect of structural and vibrational properties of solid pentaerythritol by molecular dynamics simulations

The molecular dynamics simulations (MD) are used to calculate the structural, vibrational and thermodynamic properties of pentaerythritol (PE) crystal up to 4 GPa. The pressure effect for the cell volume, lattice constants, and molecular geometry of solid PE are presented and discussed. It is observed that the C-C bonds has maximum variation, followed by C-H and C-O bonds, which means decomposition of the initial explosion may begin with the C-C bonds. The vibrational frequencies at ambient conditions slightly more than experimental results, and the pressure-induced frequency shifts of these modes are discussed.