The Pippard relations (CP vs. ?P and ?P vs. ?T) are examined at various temperatures up to 1200 K at zero pressure (P = 0) for the cubic gauche nitrogen. The specific heat (CP) is related to the thermal expansion (?P) and ...

The ? – ß structural transition occurs in quartz at TC = 846 K. The frequency of the soft mode associated with the volume increase, decreases with increasing temperature as the transition temperature is approached. In this ...

We calculate in this study the pressure dependence of the frequencies for the Raman modes of A (Ag), B (Ag, B2g) and C (B1g, B3g) at constant temperatures of 274 and 294K (room temperature) for the solid phase I of benzene. ...