Prediction of metastable phase formation in an immiscible Cu–Cr system from interatomic potential and ab initio calculation

Ab initio calculation was performed to predict the structures, lattice constants, and cohesive energies of metastable Cu₇₅Cr₂₅ and Cu₅₀Cr₅₀ phases. An n-body Cu–Cr potential was derived through fitting to some ab initio calculated results and was capable of reproducing some intrinsic properties of the Cu–Cr system. Based on the derived potential, molecular dynamics simulations predicted that for a Cu_100−xCr_x alloy, the face-centered-cubic structure is more stable than the body-centered-cubic (bcc) one when 0 ≤ x ≤ 25, while the bcc structure becomes energetically favored when 25 < x ≤ 100. Interestingly, the predictions match well with the experimental observations.