Three factors appear to affect <i>n</i>-alkane molecular vibrations in CHCl<sub>3</sub>/CCl<sub>4</sub> solutions. These are: (1) Physical restriction of the νCH<sub>3</sub> and νCH<sub>2</sub> vibrations by solvent molecules. (2) Intermolecular hydrogen bonding between <i>n</i>-alkane protons and the free pair of electrons on Cl atoms of either CCl<sub>4</sub> or CDCl<sub>3</sub>. The positively charged alkane protons arise during the dipole moment changes, δ<i>P</i>/δ<i>Q</i>, occurring during a full cycle of the νCH<sub>3</sub> and νCH<sub>2</sub> modes. (3) The physical restriction of solvent molecules, which is greater in the case of CDCl<sub>3</sub> than in the case of CCl<sub>4</sub> due to a high degree of CDCl<sub>3</sub> orientation about <i>n</i>-alkane molecules due to repulsion of the C-D of CDCl<sub>3</sub> by the <i>n</i>-alkane νCH<sub>3</sub> and νCH<sub>2</sub> protons, which allows stronger C-D:Cl bonds to be formed between solute and solvent.

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