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The normal modes giving rise to the Raman optical activity (ROA) spectrum of (+)-(3R)-methylcyclohexanone in the region below $650cm-1$ have been assigned based on Raman spectra of the parent compound and five specifically deuterated isotopomers. Stereoprojections of the molecule displaced along the vibrational coordinates demonstrate that the low frequency normal modes and ROA fetures arise from deformation and torsional modes of the cyclohexane $C6(D3d)$ skeleton coupled to axial and equitorial motion of the carbonyl and methyl groups, and an additional methyl torsional mode. Calculations of ROA intensity using the Raman atomic polar tensor $model1$ will be presented and compared to experiment. $\mathrm{<mrow\; data-mjx-texclass="ORD">1</mrow>}$T. B. Freedman and L. A. Nafie, J. Chem. Phys. 78, 27 (1983).