Absorption and emission spectroscopy ofEu3+in metaphosphate glasses

Optical absorption and emission spectra of ${\mathrm{Eu}}^{3+}$ in Ba(${\mathrm{PO}}_3$ ${)}_2$, Zn(${\mathrm{PO}}_3$ ${)}_2$, and Pb(${\mathrm{PO}}_3$ ${)}_2$ glasses are reported. Judd-Ofelt intensity parameters for f-f transitions were derived from the integrated absorption spectra and used to calculate the spontaneous emission probabilities from the ${}_{}{}^5{}_{}{}^{}$ ${\mathit{D}}_0$ state. Fluorescence-line-narrowed emission excited by the ${}_{}{}^5{}_{}{}^{}$ ${\mathit{D}}_0$ ${\leftarrow }^7$ ${\mathit{F}}_0$ transition was used to study local structure around the ${\mathrm{Eu}}^{3+}$ ion. A phenomenological crystal-field analysis was conducted using ${\mathit{C}}_{2\mathit{v}}$ symmetry, and it was found that the sites occupied by ${\mathrm{Eu}}^{3+}$ in the glasses are adequately described by Brecher and Riseberg’s model. The influence of the network modifier ions (Ba, Zn, and Pb) on the major crystal-field parameter ratio (${\mathit{B}}_{22}$/${\mathit{B}}_{20}$ and ${\mathit{B}}_{44}$/${\mathit{B}}_{40}$) is discussed. Furthermore, it was shown that the network modifier ions affect the properties of the Eu-O bond, and, consequently, the crystal-field strength.