Magnetic moments of transition impurities in antiperovskites

Starting from a first principles electronic structure calculation for superconducting antiperovskite MgCNi3 and using a simple Hartree–Fock approximation, we calculate the magnetic moment of transition impurities T in the dilute limit. The calculation shows that Co impurities are non-magnetic and for the remaining ones at least a small moment exists. Experimental studies of the change with concentration of the superconducting temperature Tc may indicate, for non-magnetic impurities, a d-wave behavior of these superconductors.