| Popis: |
Low concentrations of nickel dissolved in alkali silicate liquids at atmospheric conditions go into solution as Ni/sup +2/ ions. The observed optical absorption spectra indicate that Ni/sup +2/ is insensitive to site distortion introduced by changes in the Na/sub 2/O/SiO/sub 2/ ratio. Raman data, however, show that Ni/sup +2/ acts as a network modifier in sodium silicate melts. Comparison of spectra for Ni/sup +2/ in several glass types indicates that the optical parameters, B and Dq, are a function of the bond strength of the glass network. However, the bonding requirements of Ni/sup +2/ probably have some effect on the site geometry and energy level diagrams calculated assuming octahedral coordination are consistent with observed spectra. |
