A theoretical study of ethylene, cyclopentene and 1-amino-3-cyclopentene adsorption on the silicon surface

Abstract

In this paper we report on a comparative ab initio study of the adsorption of ethylene, cyclopentene and 1-amino-3-cyclopentene on the silicon 100 surface. Accurate calculations of the reaction path have been carried out using a cluster model for the surface dimer (Si 9 H 12 ) and Gaussian-type basis functions. The dependence of the computed reaction path on the theoretical method is investigated; activation energies turn out to be quite independent of the method, and general trends can be found for the three systems studied: the larger difference is found between linear and cyclic alkenes. Periodic calculations with plane waves are also performed on periodic slabs, finding an adsorption energy in fair agreement with the cluster model. The surface band structure is carefully studied: a strong dispersion is found along some directions for highly covered surfaces, in good agreement with the experimental data available for ethylene. Also in this case, differences arise when passing from linear to cyclic alkenes, while the second substituent on the cycle has very limited effects.

Adsorption of small hydrocarbon molecules on Si surfaces: Ethylene on Si(001)

“…In agreement with other calculations, 9,13,14,32 we find that for 0.5 ML coverage, the most stable adsorption configuration for C 2 H 4 is the on-top configuration, with the molecule lying on top of one out of two silicon dimers. For the 1 ML coverage ͑one C 2 H 4 molecule per silicon dimer͒ instead, the bridge configuration is the less energetic one ͑see Fig.…”

Electronic and optical properties of acetylene and ethylene on Si(001)

“…For both ethylene and acetylene covered surfaces, we find [3] that at low coverage the binding energy of the on-top geometry is larger than that of the bridge, while the opposite happens at full coverages, in agreement with other calculations [5][6][7][8][9][10][11][12][13][14][15]. The adsorption energies per adsorbed geometry are listed in Table 1.…”

Site‐Specific Reactivity of Ethylene at Distorted Dangling‐Bond Configurations on Si(001)

“…The reactivity in this system has also been investigated by using finite cluster approaches for the surface [7g,i,k–m] . However, most of these calculations yield a diradical mechanism with a transition‐state energy above the reference zero point.…”