Full-potential LMTO study on the electronic structure of heavy-fermion compound LiV2O4

The electronic structure of heavy fermion compound LiV₂O₄ has been calculated using a self-consistent full-potential LMTO method. The results show that the conduction bands in this compound are formed from V 3 d states with a bandwidth of 2.5 eV. The symmetric characteristics of conduction bands are of t_2g in principle. The energy gap between conduction bands and fully occupied oxygen 2p bands is 1.9 eV. The band dispersions near Fermi energy display complicated structures. Furthermore, the N( E_F) and y_cal are 11.1 (states/eV/f.u.) and 26.7 mJ/mol.K₂ determined numerically by LDA calculation, respectively. It is insufficient to clarify the origin of local moment in LiV₂O₄ from plain LDA calculations. In addition to the above LDA calculation, we also found a LSDA solution of LiV₂O₄ that is lower in total energy than that of LDA calculation. Similarly, LSDA + GGA calculation yields almost the identical result as that in LSDA. We conclude that the mechanism responsible for heavy fermion properties in LiV₂O₄ might be somewhat different from the plain Kondo mechanism in conventional 4f and 5f heavy fermion compounds and perhaps the quantum transition might play an adequate role in heavy-ferrnion behaviors in LiV₂O₄.