title: The molecular rotational motion of liquid ethanol studied by ultrafast time resolved infrared spectroscopy.
abstract: In this report, ultrafast time-resolved infrared spectroscopy is used to study the rotational motion of the liquid ethanol molecule. The results showed that the methyl, methylene, and CO groups have close rotational relaxation times, 1-2 ps, and the rotational relaxation time of the hydroxyl group (-OH) is 8.1 ps. The fast motion of the methyl, methylene and CO groups, and the slow motion of the hydroxyl group suggested that the ethanol molecules experience anisotropic motion in the liquid phase. The slow motion of the hydroxyl group also shows that the hydrogen bonded network could be considered as an effective molecule. The experimental data provided in this report are helpful for theorists to build models to understand the molecular rotational motion of liquid ethanol. Furthermore, our experimental method, which can provide more data concerning the rotational motion of sub groups of liquid molecules, will be useful for understanding the complicated molecular motion in the liquid phase.
authors.affiliation: State key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, China. kjyuan@dicp.ac.cn.
authors.forename: Gang-Hua
authors.identifier: http://orcid.org/0000-0001-6665-8196
authors.initials: GH
authors.lastname: Deng
authors.affiliation: State key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, China. kjyuan@dicp.ac.cn and Tongji Zhejiang College, Jiaxing 314000, Zhejiang, China.
authors.forename: Yuneng
authors.initials: Y
authors.lastname: Shen
authors.affiliation: State key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, China. kjyuan@dicp.ac.cn.
authors.forename: Zhigang
authors.initials: Z
authors.lastname: He
authors.affiliation: Institute of Chemistry & Chemical Engineering, Bohai University, Jinzhou 121000, China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: State key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, China. kjyuan@dicp.ac.cn.
authors.forename: Bo
authors.initials: B
authors.lastname: Jiang
authors.affiliation: State key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, China. kjyuan@dicp.ac.cn.
authors.forename: Kaijun
authors.identifier: http://orcid.org/0000-0002-5108-8984
authors.initials: K
authors.lastname: Yuan
authors.affiliation: State key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, China. kjyuan@dicp.ac.cn.
authors.forename: Guorong
authors.initials: G
authors.lastname: Wu
authors.affiliation: State key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, China. kjyuan@dicp.ac.cn.
authors.forename: Xueming
authors.initials: X
authors.lastname: Yang