title: Thermodynamic factors limiting the preservation of aromaticity of adsorbed organic compounds on Si(100): example of the pyridine.
abstract: Using pyridine as an example, a thermodynamic analysis of the low temperatures adsorption of aromatic organic molecules with a N atom on the Si(100) surface is presented. This study is restricted to the case of an equilibrium with the gas phase. Dative attachment which is the only way to preserve aromaticity is the more stable form of adsorbed pyridine in dilute solutions at low temperatures. Two factors limit the domain of stability of dative attachment: repulsive interactions between dative bonds prevent them from being present in concentrated solutions while aromaticity contributes to a decrease in the entropy, which explains the vanishing of dative bonds at high temperatures even in dilute solutions.
authors.affiliation: Laboratoire de Chimie Physique - Matiere et Rayonnement, Universite Pierre et Marie Curie 11, rue Pierre et Marie Curie, 75231 Paris Cedex 05, France. romain.coustel@iemm.univ-montp2.fr
authors.forename: R
authors.initials: R
authors.lastname: Coustel
authors.forename: S
authors.initials: S
authors.lastname: Carniato
authors.forename: G
authors.initials: G
authors.lastname: Boureau
mesh_terms: D000327:Adsorption; D001555:Benzene Derivatives / Q000737:chemistry*; D011725:Pyridines / Q000737:chemistry*; D011789:Quantum Theory; D012825:Silicon / Q000737:chemistry*; D013499:Surface Properties; D013816:Thermodynamics
chemical_list: D001555:Benzene Derivatives; D011725:Pyridines; C023666:pyridine; D012825:Silicon