title: [Effect of pressure on electron-phonon coupling constants of all-trans-beta-carotene].
abstract: The present paper cited that R Tubino and other people introduced a kind of electron-phonon coupling constants with dimension, which can establish the relation with the Huang-Rhys factor and calculate the electron-phonon coupling constants of every C-C bond vibration mode. There are many reports about the visible absorption and Raman spectra of all-trans-beta-carotene with pressure. But the study about the Raman scattering cross section and the Huang-Rhys factor with pressure have not been reported now. Visible absorption and Raman spectra of all-trans-beta-carotene were measured in carbon disulfide in the pressure range from 0. 04 to 0. 60 GPa. The results indicated that the visible absorption spectra of beta-carotene in nonpolar solvent carbon disulfide are red-shifted with pressure increasing, but the frequency shifts towards higher frequencies in the Raman spectra, the Raman scattering cross section decreases, Huang-Rhys factor increases, and the electron-phonon coupling constants of CC bond vibration modes increase. The mechanism is that all-trans-beta-carotene caused by compression and a decrease in the structurally ordered properties of the molecules leads to narrow energy gap of the pi, shortens effective conjugation length, hinders delocalization of pi-electron, decreases the Raman scattering cross section, and increases the Huang-Rhys factor and the electron-phonon coupling constants.
authors.forename: Mei-Jiao
authors.initials: MJ
authors.lastname: Sun
authors.forename: Kai
authors.initials: K
authors.lastname: Wang
authors.forename: Sheng-Nan
authors.initials: SN
authors.lastname: Xu
authors.forename: Guan-Nan
authors.initials: GN
authors.lastname: Qu
authors.forename: Shuo
authors.initials: S
authors.lastname: Li
authors.forename: Cheng-Lin
authors.initials: CL
authors.lastname: Sun
authors.forename: Mi
authors.initials: M
authors.lastname: Zhou
authors.forename: Zuo-Wei
authors.initials: ZW
authors.lastname: Li
mesh_terms: D002246:Carbon Disulfide; D004583:Electrons; D060739:Phonons; D011312:Pressure; D012997:Solvents; D013059:Spectrum Analysis, Raman; D014732:Vibration; D019207:beta Carotene
chemical_list: D012997:Solvents; D019207:beta Carotene; D002246:Carbon Disulfide