  Absorption, luminescence and Raman spectra of interstitial bismuth atoms,
$\mathrm{Bi}^{0}$, and negatively charged dimers, $\mathrm{Bi}^{2-}$, in
alumosilicate, germanosilicate, phosphosilicate and phosphogermanate glasses
networks are calculated by time-dependent density functional method. On grounds
of this calculation an extension of our previously suggested model of broadband
near-IR luminescence in bismuth-doped glasses is put forward.

Materials Science