English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Kinetic equations governing time evolution of positions and momenta of atomsin extended systems are derived using quantum-classical ensembles within theNon-Equilibrium Statistical Operator Method (NESOM). Ions are treatedclassically, while their electrons quantum mechanically; however, thestatistical operator is not factorised in any way and no simplifyingassumptions are made concerning the electronic subsystem. Using this method, wederive kinetic equations of motion for the classical degrees of freedom (atoms)which account fully for the interaction and energy exchange with the quantumvariables (electrons). Our equations, alongside the usual Newtonian-like termsnormally associated with the Ehrenfest dynamics, contain additional terms,proportional to the atoms velocities, which can be associated with theelectronic friction. Possible ways of calculating the friction forces which areshown to be given via complicated non-equilibrium correlation functions, arediscussed. In particular, we demonstrate that the correlation functions aredirectly related to the thermodynamic Matsubara Green's functions, and thisrelationship allows for the diagrammatic methods to be used in treatingelectron-electron interaction perturbatively when calculating the correlationfunctions. This work also generalises previous attempts, mostly based on modelsystems, of introducing the electronic friction into Molecular Dynamicsequations of atoms.

Non-equilibrium statistical mechanics of classical nuclei interacting with the quantum electron gas