Tc for heavy Fermion superconductors linked with other physical properties at zero and applied pressure

The superconducting transition temperature T-c has earlier been correlated with coherence length and effective mass for a series of heavy fermion (HF) materials at atmospheric pressure. Here, a further physical property, the dc electrical conductivity sigma (T-c), is one focal point, another being the pressure dependence of both T-c and sigma (T-c) for several HF materials. The relaxation time tau (T,) is also studied in relation to an Uncertainty Principle limit, involving only the thermal energy k(B)T(c) and Planck's constant.