Energy Functionals: Gradient Expansions and Beyond
The determination of the ground state energy and the ground state electron density distribution of a many-electron system in a fixed external potential is a problem of major importance in condensed matter physics. For a given Hamiltonian and for specified boundary conditions, it is possible in principle to obtain directly numerical solutions of the the Schrodinger equation. Even with current generations of computers, this is feasible in practice only for systems of rather small total electron number. Of course, a variety of alternative methods, such as self-consistent mean field theories, also exist. However, these are approximate.
KeywordsDensity Functional Theory Ground State Energy Thermodynamic Limit Local Density Approximation Finite Temperature
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