In the case of thermal energy atomic scattering from solid surfaces (TEAS) the determination of the exact interaction potential is one of the most important aims. The short range repulsive and long range attractive parts of the interaction potential are responsible for the diffractive scattering and the bound state resonances, respectively. To verify the reliability of the repulsive part of potential one has to investigate the diffraction pattern. The attractive part of potential requires an indirect way of investigation. An appropriate indirect way is based on the comparison of the time of flight (TOF) measurement to a time dependent quantum mechanical wave packet model, because the bound states cause dwelling of atoms near the surface. The model is composed of a wave packet and of an interaction potential describing the atomic beam and the solid surface, respectively. The time dependent Schrödinger equation (TDSE) governs the wave packet propagation[1][2]. Solving numerically TDSE the TOF measurement has been simulated. At the detector region - e.g. in the direction of the specular peak - the relative intensity can be calculated as a function of time choosing a time step short enough.

[1] G. Varga, Applied Surface Science, (1999) vol.144-145 p. 64-68.
[2] G. Varga, Surface Science, (1999) vol. 441 p. 472-478.