title: The effect of polarization on multiple hydrogen-bond formation in models of self-assembling materials.
abstract: We report density functional theory calculations at the B3LYP/D95(d,p) level on several different cyclic H-bonding dimers, where the monomers of each are connected by a pair of N-H···O=C H-bonding interactions, and the H-bonding donors and acceptors on each monomer are separated by polarizable spacers. Depending on the structures, the individual H-bonds vary in strength (enthalpy) by over a factor of four, from 2.41 to 10.99 kcal/mol. We attribute most of the variation in interaction energies to differences in the extent of polarization due to each of the H-bonds, which can either combine constructively or destructively. The dipole-dipole interactions between the pair of H-bonds also contribute somewhat to the relative stabilities. The relevance of these results to the design of self-assembling materials is discussed.
authors: Department of Chemistry, Hunter College and the Graduate School, City University of New York, 695 Park Avenue, New York, New York 10065, USA.
authors: Yung-Fou
authors: YF
authors: Chen
authors: J J
authors: JJ
authors: Dannenberg
mesh_terms: D019281:Dimerization; D005559:Formamides / Q000737:chemistry*; D006033:Glycylglycine / Q000031:analogs & derivatives*; D006860:Hydrogen Bonding; D008958:Models, Molecular; D011789:Quantum Theory
chemical_list: D005559:Formamides; D006033:Glycylglycine