A molecular dynamics study of the chemisorption of C2H2 and CH3 on the SI(001)-(2 × 1) surface

Chemisorption of C 2 H 2 and CH 3 molecules onto the dimerized (001) surface of silicon has been simulated using the extended Brenner potential. For reference, chemisorption energies and minimum-energy geometries have also been obtained from Hartree-Fock and Becke3LYP DFT calculations performed with the Gaussian-94 suite. Various chemisorption sites have been identified. Optimal C 2 H 2 chemisorption was found to occur in a cross-dimer configuration, parallel to the dimer rows. Optimal CH 3 chemisorption occurred with the CH 3 bonding directly to the surface dangling bonds. A second-layer chemisorption site for CH 3 has also been identified, which may be important in the formation of diamond films on a silicon substrate.