title: Hydrophobic-hydrophilic interactions of water with alkanethiolate chains from first-principles calculations.
abstract: The interaction of water with alkanethiolate chains is studied from first principles. A detailed analysis is performed by optimizing the structure of small water clusters, one-dimensional water chains, and ordered and disordered thin water layers adsorbed on hydroxyl(OH)- and methyl(CH3)-terminated alkanethiol monolayers. The hydrophilic/hydrophobic character of these two different substrates is investigated by means of an energetic analysis combined with hydrogen-bond counting. On the hydrophilic OH-terminated alkanethiol surface, zigzag, one-dimensional water chains and disordered thin water layers are the energetically favored structures. The ab initio results can be used to determine the optimal value of the empirical parameters characterizing a suitable force field to be used in classic molecular dynamics simulations.
authors.affiliation: Dipartimento di Fisica G. Galilei, Università di Padova via Marzolo 8, 35131 Padova, Italy. psil@pd.infn.it
authors.forename: Pier Luigi
authors.initials: PL
authors.lastname: Silvestrelli
authors.forename: Francesco
authors.initials: F
authors.lastname: Ancilotto
authors.forename: Flavio
authors.initials: F
authors.lastname: Toigo
authors.forename: Carlo
authors.initials: C
authors.lastname: Sbraccia
authors.forename: Takashi
authors.initials: T
authors.lastname: Ikeda
authors.forename: Mauro
authors.initials: M
authors.lastname: Boero
mesh_terms: D000327:Adsorption; D000473:Alkanes / Q000737:chemistry*; D003198:Computer Simulation; D006860:Hydrogen Bonding; D057927:Hydrophobic and Hydrophilic Interactions; D008956:Models, Chemical; D013438:Sulfhydryl Compounds / Q000737:chemistry*; D013499:Surface Properties; D014867:Water / Q000737:chemistry; D017155:Wettability
chemical_list: D000473:Alkanes; D013438:Sulfhydryl Compounds; D014867:Water