Premium
Dynamical extensions of the thomas–fermi theory
Author(s) -
Lundqvist S.
Publication year - 2009
Publication title -
international journal of quantum chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.484
H-Index - 105
eISSN - 1097-461X
pISSN - 0020-7608
DOI - 10.1002/qua.560090806
Subject(s) - basis (linear algebra) , physics , simplicity , statistical physics , electron , quantum , thomas–fermi model , fermi gamma ray space telescope , classical mechanics , ground state , quantum mechanics , fermi surface , mathematics , geometry
The first part reviews the hydrodynamical approach, considering the excitations of the electrons as small density oscillations around the ground state density. For high‐frequency perturbations, which will induce plasma‐type motions in the system, it is not an adequate procedure to describe the dynamics in terms of local changes in the static pressure. A formulation is proposed in which one retains the physical simplicity of the Thomas–Fermi approach in the treatment of the electrostatic forces but includes the quantum dynamics of the system in a way which is in principle exact within the linear response approximation. This formulation forms the basis for approximations at various levels. Applications to surface problems and to atomic systems are discussed briefly.