A theoretical study of c-C_5H_8 adsorption on Ge (001 )-2 ×1 and on dimer vacancies on the surface: Electronic structure and bonding

摘要

In this work we analyzed the geometry and the chemical interactions for c-C_5H_8 adsorption on Ge (001), using density functional theory calculations (DFT). We examined the changes in the atomic interactions using a slab model. We considered two cases, the cyclopentene adsorption on Ge(001) and on dimer vacancies on the surface. We found an average distance H-Ge, -C-Ge and =C-Ge of 1.50,1.70 and 1.65 A, respectively, on dimer vacancies; and an average =C-Ge distance of 2.05 A on Ge-Ge dimer. We also computed the density of states (DOS) and the DOS weighted overlap populations (OPDOS) corresponding to C-C, C-Ge, C-H, and Ge-Ge bonds. During adsorption the main contribution are the C=C double bond in both cases, and the next C and the H's belonging to this bonds in the case of adsorption on dimer vacancies. The orbital contribution includes participation of the 2p_y and 2p_z orbitals corresponding to unsaturated C atoms, 2p_z corresponding to side saturated C, and the 4p orbitals of Ge for the adsorption on dimer vacancies; 2s and 2p_z orbitals corresponding to double bond C atoms, 4s and 4p_z orbitals of Ge for the adsorption on Ge(0 01).