Description of light-element magnetic systems via density functional theory plus U with an example system of fluorinated boron nitride: An efficient alternative to hybrid functional approach
| Autor: | Hong Jiang, Xiaojun Xin, Wanxue Li, Hongyan Wang, Yong Zhao, Chunsheng Guo |
|---|---|
| Rok vydání: | 2018 |
| Předmět: |
Physics
General Computer Science General Physics and Astronomy 02 engineering and technology General Chemistry 021001 nanoscience & nanotechnology 01 natural sciences Electron localization function Fock space Hybrid functional Condensed Matter::Materials Science Computational Mathematics chemistry.chemical_compound Atomic orbital chemistry Mechanics of Materials Boron nitride 0103 physical sciences General Materials Science Density functional theory Statistical physics Local-density approximation Element (category theory) 010306 general physics 0210 nano-technology |
| Zdroj: | Computational Materials Science. 146:84-89 |
| ISSN: | 0927-0256 |
| DOI: | 10.1016/j.commatsci.2018.01.003 |
| Popis: | It is well known that for light-element magnetic materials density functional theory (DFT) in the local density approximation or generalized gradient approximation (LDA or GGA) underestimates the electron localization effects and tends to give misleading results. Hybrid functionals such as Heyd-Scuseria-Ernzerhof (HSE) perform much better while being computationally expensive, especially for extended systems. In order to go beyond semi-local DFT without needing to calculate the expensive Fock exchange, here we explore the performance of the more efficient GGA plus the Hubbard U correction (GGA+U) approach to light-element magnetic materials by considering fluorinated boron nitride (F-BN) sheets and nanotubes as model systems. By applying the Hubbard U correction to the N-2p orbitals with the value of U determined by fitting the HSE results in a particular F-BN sheet, it is found that the GGA+U approach shows a great improvement to GGA in describing the magnetic properties of F-BN systems with an accuracy close to that of the HSE hybrid functional approach. It indicates the possibility of using the ad hoc correction approach as an efficient alternative to study light-element magnetic materials, especially for large systems where calculations based on hybrid functionals become cost-demanding. |
| Databáze: | OpenAIRE |
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