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Raman frequency shifts calculated from the volume data in naphthalene

The Raman frequencies for modes of symmetry Ag and Bg are calculated as functions of temperature (at atmospheric pressure) and pressure (at room temperature) using the observed volume data from the literature through the mode Gruneisen parameters in naphthalene. By determining the temperature and pressure dependence of the isobaric (gamma(P)) and isothermal (gamma(T)) mode Gruneisen parameters, respectively, the Raman frequencies of the modes which were calculated, are in good agreement with the observed frequencies considered in naphthalene. Our results show that the Raman frequencies for the modes studied, can be predicted from the volume data by means of the mode Gruneisen parameters. This also leads to predicting the temperature dependence of the thermal expansion (alpha(P)) and the pressure dependence of the isothermal compressibility (K-T) from the frequency shifts, (1/v)(partial derivative v/partial derivative T)(P), and (1/v)(partial derivative v/partial derivative P)(T), respectively, which can be measured accurately in naphthalene.