Infrared transmission study of crystal-field excitations in Sm1+xBa2-xCu3O6+y -: art. no. 054528

Absorption bands, corresponding to the crystal-field (CF) excitations of the Sm3+ ions in SmBa2Cu3O6, have been observed by infrared transmission spectroscopy and assigned to transitions from the lowest energy levels of the H-6(5/2) multiplet to the excited multiplets H-6(7/2), H-6(9/2), H-6(11/2), H-6(13/2), F-6(7/2), and F-6(9/2) Of Sm3+ ions on the regular D-4h-symmetry sites and the C-4v-symmetry Pa sites. A set of the CF parameters that fits the levels in the regular sites and reproduces the magnetic susceptibility anisotropy has been derived. The CF interaction parameters in the Sm/Ba sites have been modeled by combining the superposition model and an ab initio method based on the density-functional calculations.