Abstract

Molecular dynamics techniques have been developed to simulate accurately laser-induced chemistry at surfaces with the full complexity of multidimensional interactions. Equations of motion are integrated explicitly for a slab of about fifty atoms with additional adsorbate molecules. Stochastic boundary conditions incorporate energy flow to the remaining bulk atoms and permit transient heating effects to be included correctly. Infrared laser excitation is described by an applied oscillatory external force that drives the dipole moment of the system. The simultations reveal directly the extent of disequilibrium achieved by short-pulse laser excitation. Predictions are made of situations where selective (nonthermal) desorption may be possible.

© 1987 Optical Society of America