Molecular dynamics simulations have been extensively used to study phonons and gain insight, but direct comparisons to experimental data are often difficult, due to a lack of accurate empirical interatomic potentials for different systems. As a result, this issue has become a major barrier to realizing the promise associated with advanced atomistic-level modeling techniques. Here, we present a ...

The structural stability of ternary compounds Nd2Fe17 xCrx is evaluated by using a series of quasi-ab initio interatomic potentials. The results show that the substitution of Cr atoms for Fe almost does not change the crystal symmetry significantly and the calculated structural parameters of Nd2Fe17 xCrx correspond well to experimental data. The site preference of Cr atom is further evaluated a...

A series of molecular-dynamics simulations using a many-body interatomic potential has been performed to investigate the behavior under load of several ^001& and ^011& symmetrical tilt grain boundaries ~GB’s! in diamond. Cohesive energies, the work for fracture, maximum stresses and strains, and toughness as a function of GB type are evaluated. Results indicate that special short-period GB’s po...

2014 The depolarization, broadening and shift constants of the 5 2P1/2 ~ 5 2S1/2 resonance line perturbed by rare gases are calculated in the semi-classical approximation when neglecting the excitation transfer to the 2P3/2 state in the energy range 100-1 000 K. Trajectory effects are discussed. The calculations have been performed with the interatomic potential recently published by Baylis [1]...

The indirect RKKY interaction in a layered metal with nearly nested (almost squared) Fermi surface is evaluated analytically. The final expressions are obtained in closed form as a combination of Bessel functions. We show that the expected “2kF ” oscillations occur as the far asymptote of our expressions, where a value of the effective Fermi momentum kF depends on the direction in r−space. We d...

We present a methodology for fitting interatomic potentials to ab initio data, using the particle swarm optimization (PSO) algorithm, needing only a set of positions and energies as input. The prediction error of energies associated with the fitted parameters can be close to 1 meV/atom or lower, for reference energies having a standard deviation of about 0.5 eV/atom.We tested ourmethod by fitti...

We have shown in the companion paper II, referred to as D-LI hereafter, that it was possible to introduce in a glass of Lennard-Jones particles, which is to be understood as a plausible model for metallic glasses, point defects that have all the characteristics of vacancies in a crystal. These defects can be introduced in the glass by removing an atom, they can jump over one or several interato...

We develop a maximum relative entropy formalism to generate optimal approximations to probability distributions. The central results consist in (a) justifying the use of relative entropy as the uniquely natural criterion to select a preferred approximation from within a family of trial parameterized distributions, and (b) to obtain the optimal approximation by marginalizing over parameters usin...

an improved interatomic potential model was proposed for molecular dynamics simulations of lithium borate melt/ glass systems. charge of ion was reconsidered and a new composition dependent ionic charge model was suggested. a new three-body potential model controlling B-O-B angles was also proposed. The three-body term functioned to avoid square network ring consisted of B-O bonds, without prev...

The fracture of carbon nanotubes is studied by atomistic simulations. In these simulations, the fracture behavior is found to be almost independent of the separation energy and to depend primarily on the inflection point in the interatomic potential. The results show moderate dependence of fracture strength on chirality. The range of fracture strains compares well with experimental results, but...