Effect of the crystal environment on the optical and magnetic properties of Nd3+ and U3+ ions

Optical, magnetic properties and the low-energy region of the electronic spectra in the Nd3+ and U3+ fluoride complexes embedded in CaF2 have been analyzed. The effect of the local charge compensation by interstitial F- could be evaluated via the crystal field (CF) distortion with respect to the ideal octahedral environment. All the result were obtained with the help of ab initio wave function calculations including spin orbit coupling (SO) via the MRCI state interaction of scalar relativistic CAS wave functions. The level of theory employed in this work shows a good correlation between the experimental and calculated spectroscopic properties allowing not only the correct determination of the f -> f transitions, but also the f -> d transitions in the absorption spectra. An analysis of the ground states and the magnetic behavior is performed using crystal-field (CF) models with parameters extracted from the ab initio calculations. The calculated g-factors are in concordance with the experimental data. (C) 2015 Elsevier Ltd. All rights reserved.