Ab Initio Molecular Dynamics Study of Temperature Effects on the Structure and Stability of Energetic Solid Silver Azide

Abstract

Ab initio molecular dynamics simulations have been performed to study the effects of different temperatures on the structure and stability of energetic solid silver azide. The results indicate that the N–N bond fission takes place at 523 K. The azide sublattice structure broke down prior to the silver sublattice. The initiation decomposition of silver azide is triggered by the N–N bond breaking. This will initiate many decomposition reactions and produce many nitrogen radicals, N2, and silver clusters. Silver azide has metallic properties at 573 K. As the temperature increases, its sensitivity becomes more and more sensitive. The calculated power spectra of the velocity autocorrelation function show that the low-frequency vibrational modes become more prominent than the high-frequency ones with increasing temperature. This would allow low-frequency vibrations and rotations to occur more freely than in the solid.