1. Magnetic ordering and metal-atom site preference in tetragonal CrMnAs: Electronic correlation effects
- Author
-
Laura Lutz-Kappelman, Gordon J. Miller, and Yuemei Zhang
- Subjects
Materials science ,Electronic correlation ,Condensed matter physics ,02 engineering and technology ,General Chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Metal ,Computational Mathematics ,Tetragonal crystal system ,visual_art ,0103 physical sciences ,Atom ,visual_art.visual_art_medium ,Condensed Matter::Strongly Correlated Electrons ,Density functional theory ,Magnetic interaction ,010306 general physics ,0210 nano-technology ,Preference (economics) ,Indirect exchange - Abstract
The electronic and magnetic structures of tetragonal, Cu2 Sb-type CrMnAs were examined using density functional theory. To obtain reasonable agreement with reported atomic and low-temperature magnetic ordering in this compound, the intra-atomic electron-electron correlation in term of Hubbard U on Mn atoms are necessary. Using GGA + U, calculations identify four low-energy antiferromagnetically ordered structures, all of which adopt a magnetic unit cell that contains the same direct CrCr and CrMn magnetic interaction, as well as the same indirect Mn⋅⋅⋅Mn magnetic interaction across the Cr planes. One of these low-energy configurations corresponds to the reported case. Effective exchange parameters for metal-metal contacts obtained from SPRKKR calculations indicate both direct and indirect exchange couplings play important roles in tetragonal CrMnAs. © 2018 Wiley Periodicals, Inc.
- Published
- 2017