|About this Abstract
||2016 TMS Annual Meeting & Exhibition
||Computational Thermodynamics and Kinetics
||The Origin of Anharmonicity in fcc Solids
||Albert Glensk, Blazej Grabowski, Tilmann Hickel, Jörg Neugebauer
|On-Site Speaker (Planned)
The ab initio calculation of finite-temperature lattice vibrations is of utmost importance for the prediction of phase stabilities. The strength of the quasiharmonic approximation is its access to vibrational free energies by a few static calculations only. The consideration of phonon-phonon interactions (anharmonicity) based on molecular-dynamics simulations is computationally challenging. In a recent wide-range ab initio study we showed that at the melting point anharmonic contributions are of the same order as quasiharmonic contributions and cannot be neglected for thermodynamic assessments. To make their evaluation feasible, we extend the quasiharmonic to a local anharmonic (LA) approximation. Employing this approach allows us to determine the free energy with meV accuracy, without loosing the advantage of static calculations. We compare both approaches for an extensive set of fcc metals and discuss the impact of phonon-phonon interactions and phonon linewidths on materials properties [A.Glensk et al., PRL 114, 195901 (2015)].
||Planned: A print-only volume