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A comprehensive, critical study of the vibrational, thermodynamic and thermoelastic properties of bcc iron is presented, using well established semi-empirical embedded-atom method potentials available in the literature. Classical molecular dynamics simulations are used to address temperature effects, where dynamical matrices are constructed as a time average of the second moment of the atomic displacements. The $C_{11}, C_{44}, C$ elastic constants are then obtained from the sound velocities along high symmetry directions in reciprocal space. Results are compared to ultrasonic measurements and highlight the limitations of the potentials considered here in describing thermoelastic properties.
We investigate the topology of the spin-polarized charge density in bcc and fcc iron. While the total spin-density is found to possess the topology of the non-magnetic prototypical structures, in some cases the spin-polarized densities are characteri
Large scale computer simulations are used to elucidate a longstanding controversy regarding the existence, or otherwise, of spin waves in paramagnetic BCC iron. Spin dynamics simulations of the dynamic structure factor of a Heisenberg model of Fe wit
The vibrational properties of graphene fluoride and graphane are studied using ab initio calculations. We find that both sp3 bonded derivatives of graphene have different phonon dispersion relations and phonon density of states as expected from the d
The vibrational density of states (VDOS) of nanoclusters and nanocrystalline materials are derived from molecular-dynamics simulations using empirical tight-binding potentials. The results show that the VDOS inside nanoclusters can be understood as t
Large-scale atomistic simulations with classical potentials can provide valuable insights into microscopic deformation mechanisms and defect-defect interactions in materials. Unfortunately, these assets often come with the uncertainty of whether the