Thermodynamic quantities at high pressures in the i and θ phases of solid nitrogen deduced by raman frequency shifts for the internal modes in literature

Abstract

The pressure dependence of the Raman frequencies of the internal modes is analyzed (T = 300 K) for the phases i and θ of solid nitrogen using the experimental data from the literature. Through the mode Grüneisen parameter, the isothermal compressibility κT, thermal expansion p and the specific heat Cp-Cv are calculated as a function of pressure using the Raman data in these phases. We obtain that the p varies linearly with the (1/υ)(∂υ/∂P) T and also that the Cp-Cv varies linearly with the p for N2. Our results show that by means of the analysis given here, the p, κT and C p-Cv can be predicted from the Raman frequency shifts for the i and θ phases of solid nitrogen. © 2013 World Scientific Publishing Company.