The scandium puzzle. What are its intrinsic properties

The heat capacities of three different electrotransport-refined Sc samples have been measured from 1 to 20 K. The resultant electronic specific heat constant (γ) and Debye temperature (thetasubD) values are (10.337+-0.015) mJ/g. K-2 and (346.7+-0.8) K respectively. The influence of Mg, Fe and Zr impurities on the heat capacity have been studied. In the case of Fe a variety of results can be obtained by changing the Fe concentration and heat treatment; both a pure Kondo and a spin-glass system appear to exist in these alloys. The effects of electron concentration changes (Mg lowers it and Zr increases it) are consistent with the theoretical band structures and appear to explain the variation of γ with Mg or Zr additions. The change in thetasub(D) with these two alloying agents is anomalous and has not yet been explained. The results of electrical resistivity measurements on electrotransport-refined Sc single crystals are also presented. (author)