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

Temperature dependences of the free energy (F), entropy (S) and heat capacity (C_v) are calculated (P=0) for organic compounds (solid benzene, naphthalene anthracene) by using quasiharmonic approximation. Contributions to those thermodynamic functions due Raman frequencies lattice modes benzene), librational (naphthalene), phonons vibrons (anthracene) taken into account in our calculations. We obtain that similar linear increase F nonlinear S C_v, occur with increasing temperature benzene naphthalene. This (F) (S, C_v) is rather different anthracene as molecular structure becomes complex (benzene-naphthalene-anthracene), expected. Our calculations approximation can be compared experiments compounds.