Optical and radiation shielding features of NiO-CdO-BaO borosilicate glasses

We report on the optical and radiation shielding features of NiO-CdO-BaO borosilicate glasses in the UV–vis-NIR range. The presence of Ni2+ cations in the octahedral site is emphasized by the absorption band at about 434–462 nm originating from 3A2g(F) → 3T1g(P) electronic transitions in the visible range. Also, this absorption band makes the present glass samples good candidates for optical filter applications within the visible range. Moreover, the most remarkable absorption band at about 966–986 nm due to Ni2+ cations in the tetrahedral site; 3T1(F) → 3A2(F) electronic transitions. The noticed increase in this absorption band reflects the increased heat-absorbing ability of the present glasses with further NiO doping. This result makes the present glass samples possible for solar thermal collectors. The reduction of the optical band gap (Eg) values from 3.16 to 2.95 eV can be explained by the creation of nonbridging oxygens produced by the existence of Ni2+ cations in the octahedral site. The electronic polarizability ( α0−2 ) and optical basicity ( ˄th ) values showed a slight increase with a further increase in the NiO: CdO ratio. The values of metallization criterion (M) decreased from 0.397 to 0.384 with more concentrations of NiO which agrees with the obtained data for Eg. The third-order nonlinear susceptibility (χ (3)) and nonlinear refractive index (n 2) values introduced an increment behavior with more concentrations of NiO. This behavior can be justified by the decreasing behavior of Eg. On the other hand, our glass samples are good attenuators against the low energy radiation, since the linear attenuation coefficient is high (from 0.449 to 0.442 cm−1) at 0.284 MeV.