AB-INITIO ELECTRONIC-STRUCTURE, MAGNETISM, AND MAGNETOCRYSTALLINE ANISOTROPY OF UGA2

Ab initio electronic structure calculations for the intermetallic comp ound UGa2 were performed using an optimized linear combination of atom ic orbitals method based on the local spin density approximation. Thre e separate calculations were done treating the uranium 5f states as ba nd states and as localized states with occupation two and three, respe ctively. In the itinerant approach, spin and orbital moments, magnetoc rystalline anisotropy, and the Sommerfeld constant were calculated and found to deviate significantly from the related experimental data. In the localized approach, crystal field parameters were obtained for th e 5f states, which have been treated by self-interaction corrected loc al-density theory. This approach with 5f(2) occupation is shown to pro vide reasonable results for the anisotropy of the susceptibility, for the field dependence of the magnetic moments, and for the Sommerfeld c onstant.