Direct calculation of electronic Raman scattering intensities inCs2NaPrCl6

Abstract

The resonantly enhanced 266 nm excited electronic Raman spectrum has been recorded for polycrystallineCs2NaPrCl6 at 10 K. Significant differences are observed in comparison with the 514.5 nmspectrum. These are rationalized by intensity calculations which, for theintermediate virtual excited (4f5d) states, utilize (I) the direct product of4f1 coreand 5d1 electronic states; (II) 4f5d coupled states obtained by using the Reidf2 and fd programs; (III) or for the initial and final(4f2) states, using the configuration-mixed wavefunctions(4f np) obtained by a configuration interaction assisted crystal field calculation. In general, thecalculated trends in intensities are fairly similar (except where the calculated corresponding energylevels differ appreciably), showing that not only the interaction between the 5d electron and the(4f)1 core in the 4f5d configuration, but also the inclusion of the4f np configuration, do not provide the dominant contributions to the electronic Raman transition intensityof the Pr3+ ion. The calculated enhancements to the intensity under 266 nm, compared with 514.5 nm,excitation differ for different transitions within a given terminal multiplet term, and canvary by several orders of magnitude. The calculations are successful in pinpointing thestrongest observed electronic Raman transitions, and provide an insight into themechanistic pathways involving intermediate states.