EMISSION PROFILE OF BK(III) IN A SILICATE MATRIX - ANOMALOUS DEPENDENCE ON EXCITATION POWER

We have been conducting spectroscopic investigations of the transurani um elements in silicate glasses. These studies included spectroscopic monitoring of the decay profiles of selected short-lived actinides. Al though the latter are not candidates for immobilization hosts, their h alf-lives make them attractive for probing certain fundamental issues. One facet of these studies has been spectroscopic investigations of B k in a silicate matrix. Optical spectroscopy has shown that the trival ent state of Bk is the stable state in this matrix, and Bk(III) exhibi ts primarily two emission bands, centered at 15 340 and 13 475 cm(-1). The relative intensities of these two bands exhibit an unusual depend ence on excitation power. At low power levels, the 13 475 cm(-1) emiss ion dominates; with increased power levels, the emission intensity of the 13 475 cm(-1) band decreases at a greater rate than the band at 15 340 cm(-1). As a result, this latter band dominates at higher excitat ion powers. A similar dependence of these two BB(III) emission bands w ith temperature has also been noted. Details of the emission profile o f Bk in this matrix and the basis for the observed power dependence ar e discussed. (C) 1998 Elsevier Science S.A.