In silico CrNF, a half-metallic ferromagnetic nitride-fluoride mimicking CrO2

Isoelectronic with CrO2, CrNF is proposed in silico based on ruffle derived structures with DFT computations. The ground state structure defined from cohesive energies is of MgUO4-type, characterized by short covalent Cr-N and long ionic Cr-F distances. Like CrO2 it is a half-metallic ferromagnet with M=2 mu(B)/FU integer magnetization with reduced band gap at minority spins. Major difference of magnetic response to pressure characterizes CrNF as a soft ferromagnet versus hard magnetic CrO2. The chemical bonding properties point to prevailing covalent Cr-N versus ionic Cr-F bonding. Different synthesis routes are examined. (C) 2014 Elsevier B.V. All rights reserved,