Generalized langevin theory for gas-solid processes: Inelastic scattering studies

The generalized Langevin equations for describing gas solid processes are recast as coupled first order differential equations, which are soluble by standard classical trajectory techniques. Energy transfer in rare gas/metal collisions is studied for three computationally simple models: the heatbath Brownian oscillator (hBo) model which includes the effects of the lattice, the Einstein or uncoupled oscillator model and the friction model. The hBo model correctly gives the qualitative behavior of the energy transfer for all collision times; the Einstein model is correct for short collision times but not long ones; and the friction model is unreliable.