کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1798653 | 1524828 | 2015 | 8 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Effect of the double-counting functional on the electronic and magnetic properties of half-metallic magnets using the GGA+U method Effect of the double-counting functional on the electronic and magnetic properties of half-metallic magnets using the GGA+U method](/preview/png/1798653.png)
• Ab initio study of half-metallic magnets.
• Role of electronic correlations.
• Double-counting term.
• Atomic-limit vs around-mean-field functionals.
Methods based on the combination of the usual density functional theory (DFT) codes with the Hubbard models are widely used to investigate the properties of strongly correlated materials. Using first-principle calculations we study the electronic and magnetic properties of 20 half-metallic magnets performing self-consistent GGA+U calculations using both the atomic-limit (AL) and around-mean-field (AMF) functionals for the double counting term, used to subtract the correlation part from the DFT total energy, and compare these results to the usual generalized-gradient-approximation (GGA) calculations. Overall the use of AMF produces results similar to the GGA calculations. On the other hand the effect of AL is diversified depending on the studied material. In general the AL functional produces a stronger tendency towards magnetism leading in some cases to unphysical electronic and magnetic properties. Thus the choice of the adequate double-counting functional is crucial for the results obtained using the GGA+U method.
Journal: Journal of Magnetism and Magnetic Materials - Volume 393, 1 November 2015, Pages 297–304