Theoretical study of laser heating and dissociation reactions in solids using ultrafast timehyphen;resolved xhyphen;ray diffraction

摘要

A theory of ultrafast timehyphen;resolved xhyphen;ray diffraction is presented. We show that for the case in which vibrational relaxation is fast, the xhyphen;ray diffraction intensities in pulse laser heating are determined by the Debyendash;Waller factor. We also show how the scattering intensities of the diffraction spots change with the position of the dissociating atoms in a timehyphen;resolved xhyphen;ray diffraction experiment studying dissociation reactions in solids. Our results show that the scattering intensities change in both the fully dissociated and the partially dissociated cases, and that timehyphen;resolved xhyphen;ray diffraction could be a useful tool in probing dissociation reactions in solids.