BLUE-GREEN ULTRAMARINE-TYPE ZEOLITES WITH DIMERIC TELLURIUM COLOR-CENTERS

We report the synthesis and spectroscopic properties of blue and green tellurium ultramarines, both possessing sodalite-type structures as t he well known blue sulfur ultramarines. Within the beta-cages of this zeolitic framework the colour-determining species are located. It is d erived in particular from Raman spectroscopy that the colour is genera ted by Te-2 as well as Te-2(-) species, both reported for the first ti me in such a stabilising matrix. We further report about a hydrotherma lly synthesised greenish tellurium-doped sodalite in which by means of UV-Vis, luminescence and Raman investigations the same ditellurium sp ecies are identified.