Abstract
The dynamical processes of electron- or photon-stimulated desorption of an adsorbate from solid surfaces are investigated in the presence of the dissipative energy transfer to the heat bath of substrate elementary excitations. The transition probability from the electronic excited states of an adsorbate to the ground state is calculated in the vicinity of the crossing point of the quasiadiabatic potential surfaces. The results are compared to the Landau-Zener theory for the nonadiabatic transition probability, where the coupling to the heat bath is found to play a significant role in the nonadiabatic behavior of desorption.