It has been known that the origianl MEAM (modified embedded atom method) interatomic potential for Ti and Zr [1] yield stable structures different from the hcp structure during molecular dynamics runs at finite temperatures [2]. The purpose of the present work is to develop a new semi-empirical interatomic potential for Ti and Zr using 2NN MEAM(second nearest neighbor MEAM) formalism [3], solving the instability problem in the original MEAM. The new interatomic potentials for Ti and Zr show stability of hcp structures and describe the bulk properties (elastic constants, structural energy differences), point defect properties (vacancy formation energy and formation volume), planar defect properties (stacking faults energy, surface energy), and thermal properties (thermal expansion coefficients, specific heat, melting point, heat of melting) of the Ti and Zr, in good agreement with relevant experimental information.
References
[1] M. I. Baskes and R. A. Johnson, Modelling Simul. Mater. Sci. Eng. 2, 147 (1994)
[2] K. Mae, T. Nobata, H. Ishida, S. Motoyama and Y. Hiwatari, Modelling Simul.
Mater. Sci. Eng. 10, 205 (2002)
[3] B.-J. Lee and M. I. Baskes Phys. Rev. B 62, 8564 (2000)