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 to introduce a “projected” free energy functional that depends on the Kohn-Sham orbitals only and that is invariant under their unitary transformations. The Liouville equation is always satisfied, guaranteeing a very efficient and robust variational minimization algorithm, that can also be extended to nonconventional entropic formulations.
- Received 7 March 1997
DOI:https://doi.org/10.1103/PhysRevLett.79.1337
©1997 American Physical Society