Density-functional theory and the v-representability problem for model strongly correlated electron-systems

TY - JOUR

T1 - Density-functional theory and the v-representability problem for model strongly correlated electron-systems

AU - Godby, R.W.

AU - Schindlmayr, A.

N1 - © 1995 American Physical Society. Published in Physical Review B and uploaded in accordance with the publisher's self archiving policy.

PY - 1995/4/15

Y1 - 1995/4/15

N2 - Inspired by earlier work on the band-gap problem in insulators, we reexamine the treatment of strongly correlated Hubbard-type models within density-functional theory. In contrast to previous studies, the density is fully parametrized by occupation numbers and overlap of orbitals centered at neighboring atomic sites, as is the local potential by the hopping matrix. This corresponds to a good formal agreement between density-functional theory in real space and second quantization. It is shown that density-functional theory is formally applicable to such systems and the theoretical framework is provided. The question of noninteracting v representability is studied numerically for finite one-dimensional clusters, for which exact results are available, and qualitatively for infinite systems. This leads to the conclusion that the electron density corresponding to interacting systems of the type studied here is in fact not noninteracting v representable because the Kohn-Sham electrons are unable to reproduce the correlation-induced localization correctly.

AB - Inspired by earlier work on the band-gap problem in insulators, we reexamine the treatment of strongly correlated Hubbard-type models within density-functional theory. In contrast to previous studies, the density is fully parametrized by occupation numbers and overlap of orbitals centered at neighboring atomic sites, as is the local potential by the hopping matrix. This corresponds to a good formal agreement between density-functional theory in real space and second quantization. It is shown that density-functional theory is formally applicable to such systems and the theoretical framework is provided. The question of noninteracting v representability is studied numerically for finite one-dimensional clusters, for which exact results are available, and qualitatively for infinite systems. This leads to the conclusion that the electron density corresponding to interacting systems of the type studied here is in fact not noninteracting v representable because the Kohn-Sham electrons are unable to reproduce the correlation-induced localization correctly.

U2 - 10.1103/PhysRevB.51.10427

DO - 10.1103/PhysRevB.51.10427

M3 - Article

SN - 2469-9950

VL - 51

SP - 10427

EP - 10435

JO - Physical Review B

JF - Physical Review B

IS - 16

ER -