SIMPLE TREATMENT OF ANHARMONIC EFFECTS ON THE SPECIFIC-HEAT

The comparison of the specific heat-temperature dependence data with the values which may be calculated using the measured values as a function of temperature for the normal mode frequencies is a difficult task since the data are gathered at constant pressure, whilst the theory is worked out at constant volume. In this work a formalism is developed which allows the calculation mentioned above to be carried out in a direct and simple manner. This formalism is successfully applied to the case of solid halogens Cl2 and Br2.