Electronic structure and magnetic ordering of the unconventional antiferromagnet Yb₃Pt₄

¹  KAUST, PSE Division - Thuwal 23955-6900, Kingdom of Saudi Arabia
²  Universidade de Brasília, ICCMP - 70904-970 Brasília, DF, Brazil
³  University College London, Department of Chemistry - 20 Gordon Street, WC1H 0AJ London, UK, EU

Received: 27 August 2009
Accepted: 20 November 2009

Abstract

Applying density functional theory within the generalized gradient approximation, we investigate the electronic and magnetic properties of the intermetallic rare-earth system Yb₃Pt₄. This material recently has been put forward as host for quantum criticality, while details of the magnetic ordering could not be established (Bennett N. C. et al., J. Magn. & Magn. Mater., 321 (2009) 2021). In this context, we investigate the effect of spin-orbit coupling and compare various spin patterns from the energetic point of view, which enables us to determine the electronic ground state of Yb₃Pt₄. The assumption of an elementary superexchange mechanism yields a magnetic-coupling constant in good agreement with the experimental ordering temperature.