Raman spectra of n‐alkanes. I. Raman intensities of longitudinal acoustic modes

Raman intensities are calculated for longitudinal acoustic modes of n‐alkanes which couple through methyl interactions with transverse acoustical modes. Calculated intensities from normal mode analysis and perturbation theory compare favorably with observed intensities. The results lend support to the method of calculating intensities of longitudinal acoustic modes of chains with structural defects in which the intensity is proportional to the square of the dot product of the atomic displacements of the LAM of the all trans conformation chain and the displacement of modes calculated for defect conformations.

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