Pressure dependence of the Raman frequencies for the modes I, II and III at constant temperatures in phase II of benzene

Temperature Dependence of the Entropy and the Heat Capacity Calculated from the Raman Frequency Shifts for Solid Benzene, Naphthalene and Anthracene

“…It has also been pointed out that under the pressure applied to molecular solids such as benzene, the intermolecular interactions can be compared in magnitude to intramolecular ones [3]. Due to the fact that for the calculation of 𝐶 𝑝 the change in the slopes of the 𝜗-P curves of the modes I,II and III as lattice modes, is significant compared to the internal modes in benzene, which we have reported [61] as also pointed out previously [4], we expect similar behaviour of the 𝐶 𝑣 for the solid benzene and naphthalene. This is because of the fact that we used in our 𝐶 𝑣 calculation also the Raman frequencies of six lattice modes (benzene) and six librational modes (naphthalene) as stated above.…”