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The uv-vis absorption and resonance Raman spectra of all-trans-β-carotene in polar solvent 1, 2-dichloroethane with iodine are measured at 293 K. The results indicate that the absorption peak of all-trans-β-carotene in the complex disappears at 460 nm and instead a new peak of the complex formed by all-trans-β-carotene and iodine is found at 1000 nm, so that the all-trans-β-carotene within the complex cannot produce the resonance Raman spectrum by 514.5 nm excitation laser. The Raman scattering cross section of CC bonds of all-trans-β-carotene taht does not form in complex decreases, its full bandwidth broadens and electron-phonon parameter increases with the increase of concentration of the complex, because when the concentration of the complex increases, the disorder increases in the solution and the molecular structural order decreases. These phenomena are analyzed using the coherent weakly damped electron-lattice vibration mode, the effective conjugation length mode as well as the theory of amplitude mode in this work.

In the paper we report on the enhanced stimulated Raman scattering of the weak-gain mode of benzene. The stimulated Raman scattering of C—H stretching vibration of benzene is observed in liquid core optical fiber by mixing toluene. The result is explained by (toluene-benzene)+ and (toluene-toluene)+ dimmer of plasma

Raman spectra of benzene have been obtained at pressure of 13 GPa. The results shows that with the increase of pressure，all the Raman bands blue shift，accompanied with the splitting and change of relative intensity of some spectral bands. For the vibrational Fermi resonance bands ν 1 + ν 6 — ν 8 ，according to the Betran theory，the unperturbed peak separation Δ 0 increases with pressure，which is due to the ratio of frequency-pressure of the combined ν 1 + ν 6 bands is larger than that of fundamental ν 8 . As a consequence，the coupling coefficient ω and the intensity ratio R f/a decrease. The Fermi resonance phenomenon disappears when the pressure is up to 11 Gpa，which can be explaned by high-pressure phase transition method. This report enriches the studies of environmental effect on the Fermi resonance，and provides positive reference value for the spectral certification and assignment.

The Raman spectra of CS 2 in C 6 H 6 is messured and the Fermi resonance of v 1 —2 v 2 in solution and in pure CS 2 is obvionsly different.The characteristic parameters are calculated by Berttern equation.It was found that with the concentration of CS 2 declining,the ratio of the spectral intensity （ R = Ｉ 655 / I 796 ） decreases and the coupling coefficient （ Ｗ ） raises, and the other parameters also change correspondingly. The analysis shows that dissipation coefficient of v 0 1 of CS 2 is affected by the concentration of C 6 H 6 . Asymmetric frequency shift of v 0 1 and 2 v 0 2 are observed in experiment,which is explained by amending the Bertran theory. This report has reference value for the molecule spectrum certification and the understanding and use of Fermi resonance theory.