Systematic approaches are presented to extract the interfacial potentials from the ab initio adhesive energy of the interface system by using the Chen–M ¨obius inversion method. We focus on the interface structure of the metal(111)/Zn O(0001)in this work. The interfacial potentials of Ag–Zn and Ag–O are obtained. These potentials can be used to solve some problems about Ag/Zn O interfacial structure. Three metastable interfacial structures are investigated in order to check these potentials. Using the interfacial potentials we study the procedure of interface fracture in the Ag/Zn O(0001) interface and discuss the change of the energy, stress, and atomic structures in tensile process. The result indicates that the exact misfit dislocation reduces the total energy and softens the fracture process. Meanwhile, the formation and mobility of the vacancy near the interface are observed.
The site preferences of the rare earth intermetallics Nd6Fe13-xTxSi(T = Co, Ni) are investigated by using interatomic pair potentials which are converted from a lattice-inversion method. Calculation shows that the order of the site preference of Co is 4d, 16 k, 16l1, and 16l2 and that of Ni is 16l2, 16l1, 16 k, and 4d in Nd6Fe13-xTxSi. Calculated lattice and positional parameters are found to agree with those reported in the literature. Furthermore, the phonon density of states for Nd6Fe13-xTxSiis also evaluated, and a qualitative analysis featuring the coordination and the relevant potentials is carried out.
The effects of Fe substitution for Co on the structural stability and the site preference of intermetallics Nd2CoT-xFex with a hexagonal Ce2NiT-type structure are studied by using a series of interatomic pair potentials. In Nd2CoT-xFex, Fe atoms are substituted for Co atoms with a strong preference for the 6h sites and the order of site preference is 6h, 4e, 4f, 2a, and 12k. Calculated lattice parameters are found to be consistent with the reported results in the literature. The variation behaviour of the Curie temperature of Nd2CoT-xFex is explained qualitatively by the exchange interaction model. The properties related to lattice vibration, such as phonon density of states and Debye temperature, are first evaluated for the Nd2Co7 xFex compounds.
This paper investigates the structural stability of intermetallics R3Ni13-xCoxB2 (R=Y, Nd and Sm) with Nd3Ni13B2-type structure and the site preferences of the transition element Co by using a series of interatomic pair potentials. The space group remains unchanged upon substitution of Co for Ni in R3Ni13-xCoxB2 and the calculated lattice constants are found to agree with reports in literatures. The calculated cohesive energy curves show that Co atoms substitute for Ni with a strong preference for the 3g sites and the order of site preference is 3g, 4h and 6i. Moreover, the total and partial phonon densities of states are first evaluated for the R3Ni13B2 compounds with the hexagonal Nd3Nil3B2-type structure.