A Bonding Study of c-C5H8 adsorption on Pt(111)

SANDRA SIMONETTI; PAULA V. JASEN; ESTELA A. GONZALEZ; ALFREDO JUAN; GRACIELA BRIZUELA

APPLIED SURFACE SCIENCE

ELSEVIER SCIENCE BV

Año: 2006 vol. 252 p. 7515 - 7522

0169-4332

The chemisorption of cyclopentane (c-C5H8) on Pt(111) has been studied using a qualitative band-structure calculations in the framework of tight-binding implementation with the YAeHMOP package. We modeled the metal surface by a two-dimensional slab of finite  thickness with an overlayer of c-C5H8, in a (3x3) di-σ geometry. The c-C5H8 molecule is attached to the surface with its C=C atoms bonded mainly with two Pt atoms while the opposite CH2 bends towards the surface. The Pt-Pt bonds in the underlying surface and the C-C bonds of c-C5H8 are weakened upon the chemisorption. A noticeable Pt-H and Pt-C interactions has been observed. We found that of Pt 5dz2 band plays an important role in the bonding between c-C5H8 and the surface, as do the Pt 6s and 6pz bands. The HOMO-LUMO bands of c-C5H8 are very dispersed, indicative of a strong interaction with the metal surface.