[Wien] Hartree-Fock and the Hubbard Model

[tran at theochem.tuwien.ac.at]

Hi,

all these methods are somehow based on the Hartree-Fock method,
which is (partially) free of self-interaction error.
The SIE with LDA/GGA is particularly large for localized d or f
electrons, such that LDA/GGA don't work well with these systems.

The onsite LDA+U and onsite hybrid are by far much cheaper than
the full hybrids.

This is a good paper to read:
http://journals.aps.org/prb/abstract/10.1103/PhysRevB.79.035103

F. Tran

On Tuesday 2016-10-25 02:09, delamora wrote:

>Date: Tue, 25 Oct 2016 02:09:24
>From: delamora <delamora at unam.mx>
>Reply-To: A Mailing list for WIEN2k users <wien at zeus.theochem.tuwien.ac.at>
>To: A Mailing list for WIEN2k users <wien at zeus.theochem.tuwien.ac.at>
>Subject: [Wien] Hartree-Fock and the Hubbard Model
>
>
>Dear WIEN2k community,
>
>From what I understand the Hubbard Model is to calculate the electronic
>repulsion inside the orbitals, specially in the 3d and 4f.
>
>Is it an approximation for the Hartree Fock exchange?
>
>If this is the case then it can be better calculated exact-exchange
>functionals (1, 2)
>
>1) 4.5.7 Onsite-exact-exchange and hybrid functionals for correlated
>electrons
>
>2) 4.5.8 Unscreened and screened hybrid functionals
>
>Cheers
>
>          Pablo de la Mora
>
>
>