Specific heat of the superconducting high pressure phase Ga II

The high pressure modification gallium II, which becomes superconducting near 6.4 K, has for the first time been investigated calorimetrically at about 35 kbar in the temperature range of liquid helium. From the data a Debye temperature_D = 178K and an electronic specific-heat coefficient =1.75 mJ/mole K² are obtained. These values are in good qualitative accord with the increased superconductingT_c with respect to that of Ga I.Work supported by the Deutsche Forschungsgemeinschaft.Dedicated to Prof. Dr. W. Buckel on the occasion of his 60th birthday.