Topology of amorphous gallium arsenide on intermediate length scales: A molecular dynamics study

Abstract

Structural correlations in amorphous gallium arsenide are investigated with molecular-dynamics simulations using a new interatomic potential function. The calculated static structure factor, in particular the height and width of the first peak which is a signature of the intermediate-range correlations, is in excellent agreement with x-ray diffraction experiments. Atomistic topology on intermediate length scales is elucidated through the analyses of shortest-path rings, partial static structure factors, and bond-angle distributions. The calculated energy difference between crystalline and amorphous systems is also in good agreement with electronic-structure calculations.

Assessment of Molecular Modeling & Simulation

“…signifies that the first peak in a-GaAs represents correlations beyond near-neighbor distances. Structural correlations in amorphous GaAs have been investigated with MD simulations using the new interatomic potential function (Ebbsjo et al 2000). The calculated static structure factor of amorphous GaAs, in particular the height and width of the first peak which is a signature of the intermediate-range correlations, is in excellent agreement with X-ray diffraction experiments, as shown in Fig.…”

“…The calculated energy difference between crystalline and amorphous systems is also in good agreement with electronic-structure calculations. Ebbsjo et al 2000).…”

“…Interatomic potentials have been developed for semiconductors such as GaAs, AlAs, and InAs (Ebbsjo et al 2000). The potentials were validated against experimental data and first-principles bulk electronic structure calculations on pressureinduced structural transformations, melting, and the cleavage energy.…”

Atomistic damage mechanisms during hypervelocity projectile impact on AlN: A large-scale parallel molecular dynamics simulation study

“…Shortest-path ring statistics have long been used to characterize amorphous systems (Deleeuw et al, 1985;Ebbsjo et al, 2000;Franzblau, 1991;Guttman, 1990;Rino et al, 1993Rino et al, , 2004. The amorphous structure is For the AlN structure at hydrostatic pressure P ¼ 0 GPa its N and Al sublattices experience very different pressures.…”

Scalable atomistic simulation algorithms for materials research

“…Graph data structures have played an important role in analyzing atomistic data [2,7,14], where vertices and edges represent atoms and bonds, respectively. Recently, we have used a shortest-path ring analysis to study intermediate-range orders in amorphous materials [8] and an edge-based indexing to detect grain boundaries in semiconductors nanocrystals [17]. …”