Universal correction for the Becke-Johnson exchange potential
Research output: Contribution to journal › Article › Scientific › peer-review
Details
| Original language | English |
|---|---|
| Article number | 044112 |
| Number of pages | 5 |
| Journal | Journal of Chemical Physics |
| Volume | 132 |
| Issue number | 4 |
| DOIs | |
| Publication status | Published - 28 Jan 2010 |
| Externally published | Yes |
| Publication type | A1 Journal article-refereed |
Abstract
The Becke-Johnson exchange potential [A. D. Becke and E. R. Johnson, J. Chem. Phys. 124, 221101 (2006)] has been successfully used in electronic structure calculations within density-functional theory. However, in its original form, the potential may dramatically fail in systems with non-Coulombic external potentials, or in the presence of external magnetic or electric fields. Here, we provide a system-independent correction to the Becke-Johnson approximation by (i) enforcing its gauge-invariance and (ii) making it exact for any single-electron system. The resulting approximation is then better designed to deal with current-carrying states and recovers the correct asymptotic behavior for systems with any number of electrons. Tests of the resulting corrected exchange potential show very good results for a hydrogen chain in an electric field and for a four-electron harmonium in a magnetic field.
Keywords
- density functional theory, electronic structure, exchange interactions (electron), DENSITY-FUNCTIONAL THEORY, COORDINATE-SPACE MODEL, STRONG MAGNETIC-FIELDS, SYSTEMS, OCTOPUS, TOOL