Abstract

Existing theories of laser-induced and/or phonon-assisted desorption are based upon one-dimensional (1D) surface potential analyses, which include a truncated harmonic potential (THP), 1D Morse potential (1MP) and master equation treatment with multiphonon transitions [1]. One of the severe limitations of these models is that any two-dimensional (2D) features of the excited adspecies are completely ignored, causing some unrealistic results. For example, THP over-estimates the transition rate, while the rate is underestimated by 1MP. In the present paper, we propose a qualitatively correct physical model which is able to effectively take into account the 2D features by introducing a dephasing factor into an anharmonic master equation.

© 1985 Optical Society of America