Comparative study of the magnetism of SrTcO3 and Ca(Sr)MnO3

Abstract By the first-principles calculations, we studied the electronic structures and the magnetic properties of SrTcO 3 and Ca(Sr)MnO 3 . We found the strikingly high Neel temperature of SrTcO 3 is mostly due to the strong Tc(4d)–O(2p) hybridizations, since the Tc-4d states are more extended than the Mn-3d states. Such Tc(4d)–O(2p) hybridizations increase the super-exchange constants, hence increased the Neel temperatures.