The lattice dynamical study of a binary type-II alloy


Akgun I., UĞUR G.

NUOVO CIMENTO DELLA SOCIETA ITALIANA DI FISICA D-CONDENSED MATTER ATOMIC MOLECULAR AND CHEMICAL PHYSICS FLUIDS PLASMAS BIOPHYSICS, cilt.20, sa.10, ss.1549-1556, 1998 (SCI-Expanded) identifier identifier

Özet

In the present paper, we have developed a new empirical many-body potential (MBP) and first used it, as an application, to investigate the lattice dynamics of f.c.c, Ni-12% Fe binary type-II alloy. The new MBP contains both two- and three-body atomic interactions. The two-body potential has been expressed by the modified form of the generalized Morse potential and the three-body potential has been described in terms of the new two-body model potential. The parameters defining the MBP for Ni and Fe have been computed following a procedure given by Akgun and Ugur, for f.c.c. structure at the lattice constant of the alloy. The radial, tangential and three-body force constants of the alloy have been calculated by the concentration averages of the computed force constants of the component metals. Finally, the phonon frequencies of the alloy along the principal symmetry directions have been computed using the calculated two- and three-body force constants. The theoretical results have been found to be in good agreement with the corresponding experimental values.