A systematic study was made of point defects in these intermetallic compounds by using molecular dynamics methods. The features which were examined included the stable defect configurations, the formation and migration energies and the vacancy migration mechanism. It was found that the Zr vacancies (interstitials) were unstable in both compounds. They spontaneously decayed to give pairs of Ni vacancies (interstitials) and antisite defects. The stable Ni vacancies had formation energies of 0.83 and 0.61eV in ZrNi and Zr2Ni, respectively. In the case of ZrNi, vacancy migration occurred preferentially in the [025] and [100] directions; with migration energies of 0.67 and 0.73eV, respectively. It was essentially a 2-dimensional process in the (001) plane. In the case of Zr2Ni, vacancy migration was 1-dimensional and occurred in the [001] direction; with a migration energy of 0.67eV. The stable interstitial configuration for both compounds consisted of a Ni atom lying on the (001) plane between 2 out-of-plane nearest-neighbor Zr atoms.

Point Defect Energetics in the ZrNi and Zr2Ni Intermetallics. C.S.Moura, A.T.Motta, N.Q.Lam, L.Amaral: Nuclear Instruments & Methods in Physics Research B, 2001, 175-177, 526-31. See also: Nuclear Instruments and Methods in Physics Research B, 2001, 180[1-4], 257-64