INFLUENCE OF SATURATION WITH HYDROGEN ON THE STRUCTURE AND SPECTROSCOPIC PROPERTIES OF OPTICAL-CENTERS IN CO-CONTAINING AND CU-CONTAINING SILICA GEL-GLASSES

In Co- and Cu-containing silica gel-glasses vitrified in air, the acti vators existed as oxide complexes of Co(II), Co(III), Cu(I) and Cu(II) . Annealing of these glasses in hydrogen at temperature less than or e qual to 800 degrees C leads to reduction of cobalt to the doubly charg ed state and reduction of copper to the metallic state. An increase in the annealing temperature by 100-300 degrees C results in a deteriora tion of the optical quality of the glass because of light scattering. (C) 1998 Elsevier Science B.V. All rights reserved.