Analysis of the raman frequency shifts for the lattice modes and vibrons related to the thermodynamic quantities in the η phase of solid nitrogen

The thermodynamic quantities of the isothermal compressibility, thermal expansion and the specific heat are calculated here as a function of pressure by using the observed Raman frequencies of the lattice modes and vibrons in the ? phase of solid nitrogen. The Pippard relations and their spectroscopic modifications are constructed, and the slope dP/dT is deduced from the Raman frequency shifts in this phase of N2. It is shown that the thermodynamic quantities can be predicted from the Raman frequency shifts, in particular, in the ? phase of solid nitrogen.