摘要
The influence of adding Fe_(2)O_(3) at the expense of Na_(2)O in sodium lead borate glasses on the structural,physical and electrical properties have been investigated.Results obtained from Fourier transform infrared(FTIR)spectra indicated that Fe_(2)O_(3) plays an important role in converting three coordinated boron atoms[BO_(3)]to four coordinated boron atoms[BO4].The physical properties such as density and molar volume helped to evaluate the compact structure of the prepared glass samples due to presence of[BO4]groups.The increase of Fe_(2)O_(3)/Na_(2)O replacements led to increasing the microhardness values and decreasing the thermal expansion coefficients of the studied glasses.The increase of Fe_(2)O_(3)/Na_(2)O replacements generally decreased the AC conductivity.That decrease might be due to converting of the three coordinated boron atoms[BO_(3)]to four coordinated boron atoms[BO_(4)].Dielectric constants of the samples might be an indication of the distortion in the coordinated boron atoms.The obtained experimental data indicated the internal structure of glass network and the change of the structure of the samples from three[BO_(3)]to four coordinated boron atoms[BO4].
