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3.1 Local Density Approximation (LDA)
For slowly varying densities it is reasonable to assume that
the macroscopic thermodynamical relations remain valid on a
local scale. In particular,
|
(3.1) |
where is the free energy density of a homogeneous fluid at density
.
Applying the Hohenberg-Kohn variational principle we find the equation
|
(3.2) |
which may be used to evaluate, for given , the local density
.
Franz J. Vesely Oct 2001
See also: "Computational Physics - An Introduction," Kluwer-Plenum 2001