Predicting Phonon Properties from Equilibrium Molecular Dynamics Simulations

Advanced Post-Processing Techniques of Molecular Dynamics Simulations in Studying Strong Anharmonic Thermodynamics of Solids

While the vibrational thermodynamics of materials with small anharmonicity at low temperatures has been understood well based on the harmonic phonons approximation; at high temperatures, this understanding must accommodate how phonons interact with other phonons or with other excitations. We shall see that the phonon-phonon interactions give rise to interesting couplingproblems, and essentially...

Investigation of isomorph-invariance in liquid methane by molecular dynamics simulation

In this paper, isomorph invariance of liquid methane is investigated by means of constant-NVT molecular dynamics simulations. According to the data extracted from simulations, equilibrium fluctuations show strong correlation between potential energy U and virial W. We also generated isomorph state points and investigated invariance of certain thermodynamic, structural, and dynamical properties....

Comparison and evaluation of spectral energy methods for predicting phonon properties

Two frequency-domain methods for predicting phonon frequencies and lifetimes using the phonon spectral energy density are described. Both methods draw input from molecular dynamics simulations and lattice dynamics calculations, but differ in the form of the phonon spectral energy density. One phonon spectral energy density expression (referred to as Φ) can be formally derived from lattice dynam...

Long Range Corrections to the Vapor-Liquid Equilibrium and Surface Tension of Methane with NVT Molecular Dynamics Simulations

Predicting phonon properties and thermal conductivity from anharmonic lattice dynamics calculations and molecular dynamics simulations

Two methods for predicting phonon frequencies and relaxation times are presented. The first is based on quasiharmonic and anharmonic lattice dynamics calculations, and the second is based on a combination of quasiharmonic lattice dynamics calculations and molecular dynamics simulations. These phonon properties are then used with the Boltzmann transport equation under the relaxation-time approxi...