The First-Principle Study on the Crystal Structures of Azido Derivatives of Benzene

Abstract

A molecular mechanics method with COMPASS and Dreiding force fields was used to predict molecular packings for the three title compounds among seven possible space groups (P21/c, P212121, P-1, Pbca, C2/c, Pna21, and P21). Then, periodic band calculations were performed on the predicted crystals using the density functional theory generalized gradient approximation with revised Perdew-Burke-Ernzerhof (DFT-GGA-RPBE) functional method. The obtained density of state (DOS) showed that the C-N3 bonds are possibly the trigger bond during thermolysis. The band gaps (ΔEg) were slightly different and hexaazidobenzene was more sensitive than the two others. Periodic calculation results on DOS were consistent with those obtained from bond dissociation energy calculations on gas molecules.