title: Steric and electronic effects in the host-guest hydrogen bonding in clathrate hydrates.
abstract: Clathrate hydrates with polar guest molecules (dimethyl ether, ethylene oxide, trimethylene oxide, tetrahydrofuran, and tetrahydropyran) were studied by means of the density functional theory. A model of a large cage of structure-I clathrate was employed. Optimal configurations of encaged guests were investigated with a focus on the host-guest hydrogen bond formation. Weak hydrogen bonds were found to be formed by each guest, while for THP a strong hydrogen bond and formation of L-defect was also observed. This is in accord with previous computational and experimental studies. Steric factors were shown to play a key role for the strength of the hydrogen bond formed. Interestingly, the host-guest binding is influenced not only by the size of a guest molecule but also by its shape. This work demonstrates that both electronic and steric properties of a polar guest should be considered for a full description of clathrate systems.
authors.affiliation: K. Gumiński Department of Theoretical Chemistry, Faculty of Chemistry, Jagiellonian University, Ingardena 3, 30060 Krakow, Poland.
authors.forename: Waldemar
authors.initials: W
authors.lastname: Kulig
authors.forename: Piotr
authors.initials: P
authors.lastname: Kubisiak
authors.forename: Lukasz
authors.initials: L
authors.lastname: Cwiklik
mesh_terms: D004583:Electrons; D004988:Ethers, Cyclic / Q000737:chemistry; D005027:Ethylene Oxide / Q000737:chemistry; D005663:Furans / Q000737:chemistry; D006860:Hydrogen Bonding; D008738:Methyl Ethers / Q000737:chemistry; D011714:Pyrans / Q000737:chemistry; D011789:Quantum Theory; D014867:Water / Q000737:chemistry*
chemical_list: D004988:Ethers, Cyclic; D005663:Furans; D008738:Methyl Ethers; D011714:Pyrans; D014867:Water; C018674:tetrahydrofuran; C033413:dimethyl ether; C005287:oxetane; D005027:Ethylene Oxide