Specific heat of the Ce(Cu 1− x Ni x ) 4 Ga alloys

The influence of the modification of the 3d electronic states in the heavy fermion compound CeCu 4 Ga by substitution of Cu by Ni is reported. It has been verified that the crystallographic structure is hexagonal of the CaCu 5 type and is preserved for all the x values in the alloys Ce(Cu 1− x Ni x ) 4 Ga. The measurements of the specific heat C p ( T ) have revealed that the huge electronic specific coefficient γ  = 3.3 J mol −1  K −2 for CeCu 4 Ga is reduced with the progressive Ni addition and follows the behavior of the hybridization parameter of the Ce f states with the conduction electrons. The analysis of the specific heat of the non‐magnetic reference compound LaCu 4 Ga has shown that including the mass correction corresponding to the change of Ce by La and Cu by Ni does not provide a correct estimation of the phonon term in the Ce(Cu 1− x Ni x ) 4 Ga alloys.