Ab initio calculation to predict the possible nonequilibrium A3B and AB3 states in the Co–Mo system

Ab initio calculations were carried out by means of the Vienna ab initio simulation package (VASP) to predict the possible nonequilibrium states in the Co–Mo system. At the composition of Co3Mo and CoMo3, the total energies are calculated for the four different structures, i.e. A15, D019, L12, and L60, as a function of the lattice constant and some possible nonequilibrium states in the Co–Mo system are predicted, i.e. at a stoichiometry of Co3Mo with D019 structure and at CoMo3 with an A15 structure. Experimentally, ion beam mixing of Co-enriched Co–Mo multilayers has resulted in the formation of a metastable hcp phase, which is in accordance with the predicted Co3Mo state and its crystalline structure as well as total energy.