title: Cooperativity between OH...O and CH...O hydrogen bonds involving dimethyl sulfoxide-H2O-H2O complex.
abstract: The cooperativity between the O-H...O and C-H...O hydrogen bonds has been studied by quantum chemical calculations at the MP2/6-311++G(d,p) level in gaseous phase and at the B3LYP/6-311++G(d,p) level in solution. The interaction energies of the O-H...O and C-H...O H-bonds are increased by 53 and 58%, respectively, demonstrating that there is a large cooperativity. Analysis of hydrogen-bonding lengths, OH bond lengths, and OH stretching frequencies also supports such a conclusion. By NBO analysis, it is found that orbital interaction plays a great role in enhancing their cooperativity. The strength increase of the C-H...O H-bond is larger than that of the O-H...O H-bond due to the cooperativity. The solvent has a weakening effect on the cooperativity.
authors.affiliation: Science and Engineering College of Chemistry and Biology, Yantai University, Yantai 264005, China. lqz02@mails.tsinghua.edu.cn
authors.forename: Qingzhong
authors.initials: Q
authors.lastname: Li
authors.forename: Xiulin
authors.initials: X
authors.lastname: An
authors.forename: Baoan
authors.initials: B
authors.lastname: Gong
authors.forename: Jianbo
authors.initials: J
authors.lastname: Cheng