Yan-mei Kang

VIRTUAL LATTICE TECHNIQUE AND THE INTERATOMIC POTENTIALS OF ZINC-BLEND-TYPE BINARY COMPOUNDS

Chens lattice inversion method is expended to calculate the interatomic potentials of zinc-blend-type binary compounds with the virtual lattice technique, which proposes a scheme to obtain the non-empirical interatomic potentials based on the first principle calculation.

Atomistic simulation of the lattice constants and lattice vibrations in RT4Al8 (R=Nd, Sm; T=Cr, Mn, Cu, Fe)

Abstract The lattice constants of the rare earth intermetallic compounds RT 4 Al 8 (R=Nd, Sm; T=Cr, Mn, Cu, Fe) with ThMn 12 -type structure were evaluated. This calculation was based on the interatomic potentials related to the rare earth and transition metals, which were obtained by a lattice inversion method. The results are in agreement with experiments. The total and partial phonon densities of states for these materials are also presented. The analysis for the inverted potentials explains qualitatively the contributions of different atoms to the vibrational modes.

Site preference and vibrational properties of ScCuxAl12−x

The phase stability and site preference of Cu in ScCuxAl12−x were studied based on the pair potentials obtained by the lattice inversion method. The lattice constants of ScCuxAl12−x with the content x were calculated and the results are in good agreement with experiment. The properties related to lattice vibration, such as the phonon density of states, specific heat and vibrational entropy, were also evaluated. The Debye and Einstein temperatures were used to characterize the acoustic branches and optic branches, respectively. In addition, several simple mechanical properties were investigated.

Ab initio interatomic potentials of cubic boron nitride

Abstract Chen’s lattice inversion method is extended to calculate the interatomic potentials of the zinc-blende-type binary compounds with a virtual lattice technique, which proposes a scheme to obtain non-empirical interatomic potentials from first principle calculations. In this paper, the interatomic pair potentials ΦN–N, ΦB–B and ΦB–N are obtained from the ab initio cohesive energy curves relevant to the three distinct BN structures. The modified Stillinger–Weber (MSW) three-body potentials are determined by the dependence of the total energy on the lattice distortion. Based on the calculated interatomic potentials, the structural properties and lattice dynamics of cubic boron nitride (c-BN) have been evaluated.

SITE PREFERENCE AND VIBRATIONAL PROPERTIES OF Ni3Al WITH TERNARY ADDITIONS Pd AND Ag

The site preferences of Ag and Pd in Ni3Al are evaluated based on interatomic pair potentials that are converted from ab initio cohesive energy and Mobius–Chens lattice inversion theorem. The calculated results are in good agreement with experimental data. Thus, the phonon density of states for (Ni,Pd)3Al and Ni3(Al,Ag), the corresponding Einstein and Debye temperatures are also evaluated, which describe phenomena associated with lattice vibrations of ternary intermetallic compounds.

Lattice vibration of Ce1−xScxFe4Al8

Abstract The lattice constants of the rare earth intermetallic compounds Ce 1− x Sc x Fe 4 Al 8 are calculated based on the interatomic potentials obtained by a lattice inversion method. The results are in agreement with experiments. Further, some simple mechanical properties such as the elastic constants and bulk modulus are also investigated for these materials. It is noted that, the phonon densities of states are first evaluated for the quarternary intermetallic compounds with ThMn 12 -type structure and a qualitative analysis for the vibrational modes is presented. This may be an attempt to predict the mechanical and thermodynamic properties for the rare earth materials with complex structures.