On the initiation of chemical reactions by electronic excitations in molecular solids

In this article we briefly review the results of theoretical simulations for the initiation of chemistry processes in high-explosive crystals from a solid-state-physics viewpoint. We analyze the possibility of initiation of chemical reactions from excited electronic states. In other words, we look for conditions that facilitate electronic excitations in the crystal. Specifically, we describe modifications to the electronic structure of RDX (cyclotrimethylene trinitramine) induced by lattice defects and by a shock wave traversing the solid. Our approach is based on ab initio Hartree-Fock band-structure calculations with electronic correlation corrections. An excitonic mechanism and a hole model, suggested earlier, are discussed in connection with the most recent experimental and theoretical advances in ultrafast optical techniques. We also consider here possible new avenues in the development of detonation theory.