Fundamentals of Density Functional Theory for T> 0 : Quantum meets Classical
- James Dufty (University of Florida, USA)
- Samuel B. Trickey (University of Florida, USA)
- Robert Evans (University of Bristol, United Kingdom)
- James Lutsko (CENOLI, Univ. Libre de Bruxelles, Belgium)
The aim of this workshop is to bring together leading members of two virtually independent communities of researchers working on Density Functional Theory: the quantum DFT community studying electronic systems mostly at zero temperature and the classical DFT community concerned with multicomponent and/or multiphase atomic, molecular and colloidal systems at non-zero temperatures. The broad objectives here include both exploration of enhanced formal developments and the potential for shared computational expertise with a particular focus on the developing interface between the two domains devoted to the subject of warm, dense matter. The format will include both formal talks and scheduled discussion sessions allowing for in-depth exploration of the various topics.
The classical and quantum DFT communities start with the same basic theorems but have developed completely independent approaches to the goal of turning these into practical computational tools. The objectives of the workshop will be devoted to exploring the different approaches taken to shared conceptual challenges including the following:
- Formal theory: How exact bounds, inequalities and exact sum rules are used to guide the development of functionals.
- Functional developments: The distinctive approaches to going beyond the local density approximation developed in the two communities.
- Comparison of two-point functionals: use of nonlocal functionals; the classical limit of the quantum functionals.
- Computational methods: State of the art techniques in each domain for solving the nonlinear Euler-Lagrange equation.
- Complex states (mixtures, phase transitions, coexistence): Warm dense matter includes coexisting atomic, molecular and free charge states. In principle these are treated by Coulomb interactions but in practice by the use of pseudo potentials, or average charge numbers. Classical mixtures have phenomenological potentials (usually pair potentials) representing the interactions among different constituents or species. Is there a middle ground for improved, practical descriptions?
- Stucture (pair correlations, density response function): use of correlation and response functions, via the Ornstein-Zernike and related equations, to develop free energy functionals.
- Collaboration: problems at the interface and across the classical/quantum boundaries e.g. multi-scale modeling.
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