Fig. 4
Heat capacity data and illustration of divergence of magnetic Gruneisen coefficient a Heat capacity data divided by temperature vs log T. The lattice contribution is estimated using a NiCoCr1.2 alloy and it is subtracted from the total measured heat capacity for NiCoCr0.8 resulting in the data shown in red. This alloy is a Pauli paramagnet outside of the critical region (see Fig. 2) that should have a very similar phonon contribution to the heat capacity.19 The low temperature heat capacity of the reference alloy, NiCoCr1.2, is well described by a Debye model with an electronic contribution characterized by γ = 9.2 mJ/mole-K2, and Θ D = 466 K. b log (Γ) vs. log (T), with a solid line illustrating the divergence of Γ ≈ T −2.5. The standard deviation (s.d.) for these data are approximately the size of each data point
