Electronic absorption spectroscopy of neodymium acetate single crystals

Electronic absorption spectra of neodymium acetate single crystals were measured at 293 and 4 K. The intensities of 4f-4f transitions were calculated and the Judd-Ofelt Ωλ parameters evaluated. These results differ in comparison with other lanthanide carboxylate compounds by relatively high 'hypersensitive' transition intensity and the Ω2 parameter value. The vibronic mechanism of the 4f-4f transitions is discussed and the role of low-energy phonons is shown. (orig.)