Ensemble Density-Functional Theory for Ab Initio Molecular Dynamics of Metals and Finite-Temperature Insulators
Year: 1997
Type: article
Abstract: A new method is presented for performing first-principles molecular-dynamics simulations of systems with variable occupancies. We adopt a matrix representation for the one-particle statistical operator $\stackrel{^}{\ensuremath{\gamma}}$ to introduce a ``projected'' free energy functional $G$ that depends on the Kohn-Sham orbitals only and that is invariant under their unitary transformations. The Liouville equation $[\stackrel{^}{\ensuremath{\gamma}},\stackrel{^}{H}]\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}0$ is always satisfied, guaranteeing a very efficient and robust variational minimization algorithm, that can also be extended to nonconventional entropic formulations.
Source: Physical Review Letters
Authors: Nicola Marzari, David Vanderbilt, M. C. Payne
Language: English
Subfield: Atomic and Molecular Physics, and Optics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W2138522514