Chemisorption Theory: Dissociation ofH2on Ti (0001)

Abstract

The chemisorption of ${\mathrm{H}}_2$ on Ti(0001) is treated with use of an ab initio configuration-interaction theory for the surface region. Dissociation of ${\mathrm{H}}_2$ occurs above the surface but more stable threefold coordination sites lie closer to the surface at ∼ 1.3 Å. Adsorption in adjacent threefold sites is less stable than in separated sites sharing only one surface atom. Bonding is predominantly with the $4s$ electrons of the metal leading to hydridic hydrogens and a polarized lattice electronic distribution.