Electronic Excitations in Initiation of Chemistry in Molecular Solids

摘要

An ab initio study is performed for the initiation of chemistry in high explosive crystals from a solid-state physics viewpoint. Specifically, we are looking for the relationship between the defect-induced deformation of the electronic structure of solids, electronic excitations, and chemical reactions under shock conditions. Band structure calculations by means of the Hartree-Fock method with correlation corrections were done to model an effect of a strong compression induced by a shock/impact wave on the crystals with and without edge dislocations. Based on the results obtained, an excitonic mechanism of the earliest stages for initiation of high explosive solids is discussed with application to cyclotrimethylene trinitramine (also known as RDX) crystal. Experimental verification of the validity of the proposed model is reported for RDX and heavy metal azides. Thus, the key role of electronic excitations facilitated by edge dislocations in explosive solids is established and analyzed. Practical applications of the suggested mechanisms are discussed.