Orbital state and magnetic properties of LiV2O4 -: art. no. 085111

LiV2O4 is one of the most puzzling compounds among transition metal oxides because of its heavy-fermion-like behavior at low temperatures. In this paper we present results for the orbital state and magnetic properties of LiV2O4 obtained from a combination of density functional theory within the local density approximation and dynamical mean-field theory (DMFT). The DMFT equations are solved by quantum Monte Carlo simulations. The trigonal crystal field splits the V 3d orbitals such that the a(1g) and e(g)(pi) orbitals cross the Fermi level, with the former being slightly lower in energy and narrower in bandwidth. In this situation, the d-d Coulomb interaction leads to an almost localization of one electron per V ion in the a(1g) orbital, while the e(g)(pi) orbitals form relatively broad bands with 1/8 filling. The theoretical high-temperature paramagnetic susceptibility chi(T) follows a Curie-Weiss law with an effective paramagnetic moment p(eff)=1.65 in agreement with the experimental results.