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Orientational and induced contributions to the depolarized Rayleigh spectra of liquid and supercooled ortho-terphenyl

S. Mossa·G. Ruocco·M. Sampoli
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Abstract

The depolarized light scattering spectra of the glass forming liquid ortho-terphenyl have been calculated in the low frequency region using molecular dynamics simulation. Realistic system's configurations are produced by using a recent flexible molecular model and combined with two limiting polarizability schemes, both of them using the dipole-induced-dipole contributions at first and second order. The calculated Raman spectral shape are in good agreement with the experimental results in a large temperature range. The analysis of the different contributions to the Raman spectra emphasizes that the orientational and the collision-induced (translational) terms lie on the same time-scale and are of comparable intensity. Moreover, the cross terms are always found to be an important contribution to the scattering intensity.

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S. Mossa, G. Ruocco, M. Sampoli. 2002-02-07. Orientational and induced contributions to the depolarized Rayleigh spectra of liquid and supercooled ortho-terphenyl. https://doi.org/10.1063/1.1493774

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