A combined theoretical and experimental study is performed for the initiation of chemistry process in high explosive crystals from a solid-state physics viewpoint. In particular, we were 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 obtained results, an excitonic mechanism of the earliest stages for initiation of high explosive solids is suggested with application to cyclotrimethylene trinitramine (also known as RDX) crystal. Experimental tests of this mechanism for AgN3 decomposition controlled by the dislocation density were worked out. The use of pulse radiolysis techniques allows us to observe pre-explosion modifications in properties and behavior of the solids. Pre-explosion conductivity and pre-explosion luminescence measurements for a series of heavy metal azides lead us to the model for the development of the decomposition chain reaction. 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.

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Laser initiation of energetic materials has a potential to shift a paradigm in the development of novel explosive technologies with a stunningly broad range of applications. Once interactions of laser irradiation with energetic materials are better understood, dramatically improved safe explosive devices, intricate high-precision tools in micromedicine, miniaturized cutting and drilling tools, synthesis of new promising materials with tailored properties, and fundamentally new concepts of converting energy become possible. We consider the interplay between optical and thermal energies, analyze the applicability of the thermal mechanism of initiation, and estimate the limits of its efficiency in the process of laser initiation of energetic materials. We propose a simple demonstration of a feasibility of nonthermal selective photoinitiation while challenging the widely popular perception of the thermal nature of laser initiation.

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