Preparation and characterisation of red glasses in the system TeO2-PbCl2

Oxide halide lead tellurite glasses of composition (TeO)(1-y)(PbCl2-zO(z/2) )(y), y = (0.17-0.64), z = (0.40-0.57) were prepared from TeO2 and PBCl2 by melting of the starting components in a platinum crucible. Chemical analys is of prepared red glassy samples leads to the following opinion: during pr eparation a reaction between TeO2 and Pb Cl-2 occurs and Pb oxides and Te c hlorides come into existence; TeCl4 attacks Pt. The products of this intera ction in the presence of Pb cause a red tinge to the synthesised glasses. O ptical properties of these glasses were characterised by transmittance meas urements in region of 0.3-7 mu m and by reflectance measurements in the reg ion of 70-1000 cm(-1). Using Kramers-Kronig analysis the wavenumber depende ncies of absorption coefficient K were determined In the region 70-1000cm(- 1) the following bands were identified A (737cm(-1)), B (650-665cm(-1)), C (600-615cm(-1)), D (340-325cm(-1)), E (120-150cm(-1)), F (85-75cm(-1)). Ban ds A, B, C and D are characteristic for tellurite glasses, the bands E, F p robably correspond with vibrations of Pb-O bonds.