On 20 Jun 2022, at 17:16, Francisco Garcia <garcia.ff....@gmail.com<mailto:garcia.ff....@gmail.com>> wrote:

Dear users, In metallic systems with a fairly sizable electronic smearing temperature T, is it accurate to claim that (i) in a single point calculation, the free energy is the representative energy of the system (due to the addition of -TS to the total energy U) No, the -TS term for the phononic entropy is missing. It is the free energy defining the finite temperature equilibrium for the purely electronic problem for fixed external potential (fixed nuclei), as in Merminâ€™s finite -T DFT. (ii) in a variable cell optimization, the enthalpy is the representative energy of the system (due to the addition of the PV term to the energy). Yes, it is the free energy of the system (minimum defines equilibrium) for T=0. Emilio Thanks! -- SIESTA is supported by the Spanish Research Agency (AEI) and by the European H2020 MaX Centre of Excellence (http://www.max-centre.eu/) -- Emilio Artacho Theory Group, Nanogune, 20018 San Sebastian, Spain, and Theory of Condensed Matter, Department of Physics, Cavendish Laboratory, University of Cambridge, Cambridge CB3 0HE, UK

-- SIESTA is supported by the Spanish Research Agency (AEI) and by the European H2020 MaX Centre of Excellence (http://www.max-centre.eu/)