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The non-coincidence $(\Delta \nu )$ of the isotropic and anisotropic peak frequencies of the Raman carbonyl band was studied for a series of alkyl benzoates. Methyl benzoate, ethyl benzoate, propyl benzoate hexyl benzoate and 2-ethylthexyl benzoate were observed over a density range of 0-95 to 1.20 g $cm-3$ at 20 and $40\circ C$. The characteristic density dependence of the value of the non-coincidence effect for each alkyl benozate correlates well with the length and branching of the alkyl side chain. In fact, it was possible to interpret the density dependence of $\Delta \nu$ in terms of packing fraction and conformational changes of the alkyl side chain.