Influence of Halogen Ions on Electrical, Magnetic and Shielding Properties of Some B2O3- V2O5- Na2O Glasses

Some sodium boro-vanadate glasses containing various halogen ions (chlorine, bromine and iodine) were prepared. These glasses were characterized by measuring the experimental densities, dc conductivities and volume-magnetic susceptibilities. Then the empirical densities, experimental and empirical molar volume values, electrical activation energies, mass- and molar-magnetic susceptibilities as well as the total mass attenuation coefficients of all glasses were calculated. The gradual increase in halogen ions act to decrease experimental density from 2.45 to 2.13 g/cm3, while it acts to increase the molar volume. It was found that, the activation energy decreased around 0.3 eV as the halogen content was increased, it decreased also ongoing from chlorine to iodine that can be ascribed to the differences in ionic radii of halogen ions, and this was confirmed by the molar volume. It was supposed that the increase in the paramagnetic character of the studied glasses with the increase of halogen content may be due to the formation of VXO3 groups. Also, the magnetic properties were found to increase as the ionic radius of the introduced halogen ions increased, and this can be attributed to the increase in the internal vacancies through the network. Correlations were established between both the activation energy and molar susceptibility with molar volume. According to the results of the mass attenuation coefficients, it was found that, the sample contains 25 mol% NaI is the best one that can be used as -ray attenuator, but only at gamma-ray energies up to 356 keV.