Model of the photostimulated fragmentation of PETN molecules in selective photoinitiation

A model of the photostimulated fragmentation of the PETN molecule irradiated by the first harmonic of a neodymium laser (1060 nm) is proposed. Photoexcitation at 1060 nm leads to the n → π* transition of the 2 p nonbinding electron of the oxygen to the π* antibonding orbital, a transition that causes the rupture of the O-N bond and the formation of NO 2 * radicals, thereby ensuring a further development of explosive decomposition. In the case of a free molecule or a molecule located on the surface of a microcrystal, the process does not require any thermal activation. In the case of a molecule at a regular lattice site, an additional activation energy (0.4 eV) is needed to overcome the potential barrier associated with the passage of through a bottleneck between the nearest-neighbor molecules.