Publications by authors named "Guan-nan Qu"

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.

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A visible absorption and Raman spectra of all-trans-beta-beta-carotene was measured in cyclohexanol solution in the temperature range from 68 degrees C to 26 degrees C. The results indicated that the visible absorption spectra are red-shifted, Raman scattering cross section increases, Huang-Ryes factor and electron-phonon coupling constants of CC bond vibration modes decreases with the temperature decreasing. The changes are interpreted using the theory of "coherent weakly damped electronic-lattice vibration model" and "effective conjugation length model".

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Raman spectra of ice VII phase were obtained at room temperature when the pressure was from 2.5 to 23 GPa. The experimental results indicate that the oxygen atoms distance do-o of ice decreased with pressure increasing,which results in that hydrogen bond is shortened, O--H bond is lengthened,force constant is reduced, and Raman spectra are red shifted.

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