Electronic excitations in shocked nitromethane

摘要: The nature of electronic excitations in crystalline solid nitromethane under conditions shock loading and static compression are examined. Density-functional theory calculations used to determine the crystal bandgap hydrostatic stress, uniaxial strain, shear strain. Bandgap lowering strain due molecular defects vacancies is considered. Ab initio molecular-dynamics simulations done all possible nearest-neighbor collisions at a front, shearing along sterically hindered slip plane. In cases, not lowered enough produce significant population excited states crystal. nearly free rotation methyl group localized highest occupied orbital lowest unoccupied play role this result. Dynamical effects have more effect on than effects, but relative molecule velocities excess 6 km/s required thermal states.