Superconductivity and Electron Interaction in the3dBand

The superconducting transition temperatures, electronic specific heats, and magnetic susceptibilities have been measured for the alloy series Cr-V, Cr-Mo, V-Mo, Ru-Fe (hcp), and Ru-Mn (hcp). These data are combined within the framework of current theoretical models, and conclusions are drawn regarding the strength of the electron phonon attraction and electron-electron repulsion in the $3d$ band. In particular, it is deduced that the superconducting transition temperature of "paramagnetic" Cr would be ∼${10}^{-6\mathrm{}}$°K, and that paramagnetic (hcp) Fe and Mn would not be superconducting at any temperature.