title: Wagging motion of hydrogen-bonded wire in the excited-state multiple proton transfer process of 7-hydroxyquinoline·(NH3)3 cluster.
abstract: In this work, the dynamics of hydrogen bonds (as well as the hydrogen-bonded wire) in excited-state tautomerization of 7-hydroxyquinoline·(NH3)3 (7HQ·(NH3)3) cluster has been investigated by using time-dependent density functional theory (TDDFT). It shows that upon an excitation, the hydrogen bond between -OH group in 7-hydroxyquinoline (7HQ) and NH3 moiety would extremely strengthened in S1 state, which could effectively facilitate the releasing of the proton from the phenolic group of 7HQ moiety to the hydrogen-bonded wire and the forming an Eigen-like cationic wire (NH3···NH4(+)···NH3) in the cluster. To fulfill the different optimal angles of NH4(+) in the wire, a wagging motion of hydrogen-bonded wire would occur in excited state. Moreover, the wagging motion of the hydrogen-bonded wire would effectively promote excited-state proton transfer reaction. As the results, an excited-state multiple proton transfer (ESMPT) mechanism containing two concerted and asymmetrical processes has been proposed for the proton transfer dynamics of 7HQ·(NH3)3 cluster.
authors.affiliation: Department of Physics, College of Mathematics and Physics, Bohai University, Jinzhou 121013, China. yhliu@dicp.ac.cn
authors.forename: Yu-Hui
authors.initials: YH
authors.lastname: Liu
authors.forename: Sheng-Cheng
authors.initials: SC
authors.lastname: Lan
authors.forename: Chun-Ran
authors.initials: CR
authors.lastname: Li
mesh_terms: D000641:Ammonia / Q000737:chemistry*; D006860:Hydrogen Bonding; D006912:Hydroxyquinolines / Q000737:chemistry*; D008958:Models, Molecular; D009038:Motion; D011522:Protons; D011789:Quantum Theory
chemical_list: D006912:Hydroxyquinolines; D011522:Protons; D000641:Ammonia; C547246:7-hydroxyquinoline