On design of molecular photo-triggers for photochemical decomposition in high explosives

Manipulation of chemical composition is a potentially efficient pathway for controlled ignition via the mechanism of photolysis in excited electronic states. Computational design methods can be used to find an optimal choice of trigger moiety – a chemical group attached to a high explosive to initiate decomposition reactions. We perform a quantum chemistry study of isolated RDX molecules chemically substituted by a series of aromatic moieties, with the aim of finding general recipes for molecular design of decomposition reaction triggers. Using the Wiberg bond indices as a comparative measure of bond strength, we study the effects of chemical composition and geometric particulars of the dyadic systems on the optical response properties and bond energies. The relation of these properties to the problem of ignition is discussed.