ePrints@IIScePrints@IISc Home | About | Browse | Latest Additions | Advanced Search | Contact | Help

Approximate VB-MO schemes for excitation gaps in Hubbard models

Srinivasan, Bhargavi and Ramasesha, S (1992) Approximate VB-MO schemes for excitation gaps in Hubbard models. In: Solid State Communications, 81 (10). pp. 831-835.

[img] PDF
APPROXIMATE_VB-MO_SCHEMES.pdf - Published Version
Restricted to Registered users only

Download (407Kb) | Request a copy
Official URL: http://dx.doi.org/10.1016/0038-1098(92)90547-M

Abstract

The excitation gaps in the singlet and triplet manifolds for finite Hubbard models in one, two and three dimensions have been obtained using different approximate configuration interaction (CI) schemes, as a function of the correlation strength, by using valence bond (VB) functions constructed over the molecular orbital (MO) basis. These are compared with numerically exact results and it is found that the scheme in which all particle hole excitations below a given threshold are included is the method of choice. The excitation energies are well reproduced, in trend as well as magnitude, particularly when the threshold equals the bandwidth of the corresponding noninteracting system.

Item Type: Journal Article
Additional Information: Copyright of this article belongs to Elsevier science.
Department/Centre: Division of Chemical Sciences > Solid State & Structural Chemistry Unit
Date Deposited: 28 Jan 2011 04:54
Last Modified: 28 Jan 2011 04:54
URI: http://eprints.iisc.ernet.in/id/eprint/35086

Actions (login required)

View Item View Item