Electronic structure of a striped nickelate studied by the exact exchange for correlated electrons (EECE) approachU. Schwingenschlögl1, C. Schuster2 and R. Frésard3
1 KAUST, PSE Division - 23955-6900 Thuwal, Kingdom of Saudi Arabia
2 Universität Augsburg, Institut für Physik - 86135 Augsburg, Germany, EU
3 Laboratoire CRISMAT, UMR CNRS-ENSICAEN(ISMRA) 6508, and IRMA, FR3095 - 14050 Caen, France, EU
received 9 October 2009; accepted in final form 25 November 2009; published December 2009
published online 4 January 2010
Motivated by a RIXS study of Wakimoto et al. (Phys. Rev. Lett., 102 (2009) 157001) we use density functional theory to analyze the magnetic order in the nickelate La5/3Sr1/3NiO4 and the details of its crystal and electronic structure. We compare the generalized gradient approximation to the hybrid functional approach of exact exchange for correlated electrons (EECE). In contrast to the former, the latter reproduces the insulating state of the compound and the midgap states. The EECE approach, in general, appears to be appropriate for describing stripe phases in systems with orbital degrees of freedom.
71.20.-b - Electron density of states and band structure of crystalline solids.
71.45.Lr - Charge-density-wave systems.
75.25.+z - Spin arrangements in magnetically ordered materials (including neutron and spin-polarized electron studies, synchrotron-source X-ray scattering, etc.).
© EPLA 2009