SPECTROSCOPIC PROPERTIES OF SE-2(2-) AND SE-2(-) IN CANCRINITE

Selenium has been introduced into the cancrinite matrix by hydrotherma l methods. Hereby uniform red-brown hexagonal crystals of very good qu ality up to 4 x 1 x 1 mm in size have been obtained, Selenium was foun d to be homogeneously distributed in cancrinite-in contrast to post-sy nthesis loading, UV/VIS and Raman investigations identify Se-2(2-) as the predominating coloring species besides Se-2(-). Because of the hig h optical anisotropy of cancrinite (perpendicular to c, parallel to c) strong polarization effects were detected. (C) 1996 Academic Press, I nc.