Elastic properties and electronic structures of antiperovskite-type InNCo3 and InNNi3

We have performed first-principles calculations to study the elasticity, electronic structure, and magnetism of InNCo3 and InNNi3. The independent elastic constants are derived from the second derivative of total energy as a function of strain, and the elastic moduli are predicted according to the Voigt–Reuss–Hill approximation. Our calculations show that the bulk modulus of InNCo3 is slightly larger than that of InNNi3 due to a smaller lattice constant for InNCo3. For InNCo3 the ferromagnetic state is energetically preferable to the non-magnetic state, while the ground state of InNNi3 is non-magnetic. This is due to the different strength of 2p–3d hybridization for the N–Co atoms in InNCo3 and the N–Ni atoms in InNNi3.