title: A study on the Fermi resonance of phenol under the effects of pressure and temperature by Raman spectroscopy.
abstract: The ν1-ν18a Fermi resonance (FR) of phenol were investigated by pressure-dependent Raman spectroscopy from atmospheric up to P=15.2GPa and temperature-dependent Raman spectroscopy from 40 down to T=-180°C, respectively. In the case of pressure, we found the Fermi coupling coefficient W, which were calculated based on the FR theory, exposed a value turnover between 1.912 and 2.244GPa in the process of increasing the pressure. This turnover phenomenon of the Fermi coupling coefficient W has been ascribed to the crystal structure of phenol evolving towards a more symmetric structure with pressure, from a structure like a pseudo-threefold helical chain at ambient pressure to like a ribbon arrangement at 1.912GPa, then to adopt a herringbone arrangement at much higher pressure. On the other hand, we also found the Fermi coupling coefficient W exhibited monotonic reduction without turnover points appearing by decreasing the temperature. The tendencies of the Fermi coupling coefficient W with temperature were in good agreement with the pressure dependence of the Fermi coupling coefficient W in the region of ambient to 1.912GPa, indicating that the effect of pressure and temperature on the FR of phenol in this region might be the same. A conformation evolving induced by pressure and temperature on the ν1 and ν18a FR of phenol have been analyzed.
authors.affiliation: College of Physics, Jilin Normal University, Siping 136000, PR China; Changchun Observatory, National Astronomical Observatories, Chinese Academy of Sciences, Changchun 130117, PR China; State Key Laboratory of Superhard Materials, College of Physics, Jilin University, Changchun 130021, PR China. Electronic address: goodldf@gmail.com.
authors.forename: DongFei
authors.initials: D
authors.lastname: Li
authors.affiliation: College of Physics, Jilin Normal University, Siping 136000, PR China.
authors.forename: Zhong
authors.initials: Z
authors.lastname: Hua
authors.affiliation: Changchun Observatory, National Astronomical Observatories, Chinese Academy of Sciences, Changchun 130117, PR China.
authors.forename: ChengZhi
authors.initials: C
authors.lastname: Liu
authors.affiliation: Changchun Observatory, National Astronomical Observatories, Chinese Academy of Sciences, Changchun 130117, PR China.
authors.forename: Cunbo
authors.initials: C
authors.lastname: Fan
authors.affiliation: State Key Laboratory of Superhard Materials, College of Physics, Jilin University, Changchun 130021, PR China.
authors.forename: ChengLin
authors.initials: C
authors.lastname: Sun
authors.affiliation: State Key Laboratory of Superhard Materials, College of Physics, Jilin University, Changchun 130021, PR China.
authors.forename: ZuoWei
authors.initials: Z
authors.lastname: Li
authors.affiliation: College of Physics, Jilin Normal University, Siping 136000, PR China. Electronic address: chenwwjj@126.com.
authors.forename: WanJin
authors.initials: W
authors.lastname: Chen
keywords: Fermi resonance (FR); High pressure; Low temperature; Phenol; Raman spectroscopy