Theoretical study of methanethiol adsorbed on GaAs(100) surface

The adsorption sites and structure of methanethiol as radical on GaAs(100) reconstructed surface was studied. The new parameterized PM6 semiempirical methodology was used. The radical molecule results in a stable on Top configuration, binding covalently to As atom on the GaAs surface. The S-As bond length optimized was 2.32 Å. The bond order S-C tends to decrease when the molecule is adsorpted on the surface.