Embedded Atom Method-Based Geometry Optimization Aspects of Body-Centered Cubic Metals

Abstract

We present embedded atom method-based geometry optimization calculations for Fe, Cr, Mo, Nb, Ta, V and W body-centered cubic metals with Finnis-Sinclair potentials. After the optimization, we determine their typical elastic constants, bulk modulus, shear modulus, Young's modulus, Poisson's ratios, elastic wave velocities and cohesive energies. Additionally, we perform a benchmark between the experiments and the available density functional theory results. In general, our results show a good consistency with previous findings on the elastic and cohesive energy properties of the considered metals.

Phase transition and elasticity of gallium arsenide under pressure

“…Ot delivers detailed knowledge about the bonding force behavior in solids 15,29 . ν = 0.25 and ν = 0.5 values are the lower limit and upper limit for central force solids, respectively.…”

“…Being dependent on this case, two typical elastic waves namely the longitudinal wave (V L ) and shear wave(V S ) arise 15 . V L has an uniform increment trend with the increasing pressure in B3 and B1 phases in Figure 7 whereas V S is increasing in the B3 phase and decreasing in the B1 phase.…”

“…[13,14] during the present work. GULP code allows wide-range property calculations for 3D periodic solids, 2D surfaces, and gas phase clusters by employing two-body, three-body, four-body, six-body, and many body (EAM) potentials 15,16 depending on the demands of research. Since Stillinger-Weber type potentials provide reliable results especially for semiconductors, we employed a recent and modified Stillinger-Weber type potential 17 to research for GaAs.…”

“…The lattice constant for GaAs was set as a 0 = 5.66 Å which is slightly higher than the experimental lattice constant a exp = 5.65 Å. Dther details of applied StillingerWeber type potential and its modified parameterization procedure can be also found in Han and Bester 17 . Ot is also possible to optimize related structures at constant pressures (includes all internal and cell variables) and constant volume (unit cell remains frozen) with GULP [1,[13][14][15][16]18] . Constant pressure optimization was performed for GaAs in our survey.…”

“…Constant pressure optimization was performed for GaAs in our survey. The geometry of cells was optimized by the Newton-Raphson method based on the Hessian matrix calculated from the second derivatives and Hessian matrix was recursively updated during optimization by using the BFGS [1,[13][14][15][16]18] algorithm. After setting the preconditions for the B3 crystal structure of GaAs, we adopted multiple runs at zero Kelvin temperature and checked the pressure ranges starting from 0 GPa up to 25 GPa.…”