title: Spectroscopic and theoretical evidence for the cooperativity between red-shift hydrogen bond and blue-shift hydrogen bond in DMSO aqueous solutions.
abstract: The cooperativity between red-shifted hydrogen bond and blue-shifting hydrogen bond in dimethyl sulfoxide aqueous solutions was studied by methods of quantum chemical calculations and infrared spectroscopy. The water molecule plays a different role in two types of hydrogen bonds: proton-donor in red-shifted hydrogen bond and proton-acceptor in blue-shifting hydrogen bond. The cooperativity is not prominent if the ring structure is formed through the OHcdots, three dots, centeredOS H-bond and CHcdots, three dots, centeredO(w) H-bond. However, if the methyl groups in the above ring structure participate in second CHcdots, three dots, centeredO(w) H-bond, the cooperativity is increased. The second CHcdots, three dots, centeredO(w) H-bond enhances OHcdots, three dots, centeredOS H-bond and weakens the first CHcdots, three dots, centeredO(w) H-bond.
authors.affiliation: Science and Engineering College of Chemistry and Biology, Yantai University, Yantai 264005, People's Republic of 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
mesh_terms: D004121:Dimethyl Sulfoxide / Q000737:chemistry*; D006860:Hydrogen Bonding; D008958:Models, Molecular; D012996:Solutions; D013057:Spectrum Analysis; D013816:Thermodynamics; D014732:Vibration; D014867:Water / Q000737:chemistry
chemical_list: D012996:Solutions; D014867:Water; D004121:Dimethyl Sulfoxide