The chemisorption of cyclopentane (c-C5H8) on Pt(1 1 1) 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 (3 x 3) di-sigma 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 5d(z)(2) band plays an important role in the bonding between c-C5H(8) and the surface, as do the Pt 6s and 6p(z), bands. The HOMO-LUMO bands Of c-C5H8 are very dispersed, indicative of a strong interaction with the metal surface. (c) 2005 Elsevier B.V. All rights reserved.