Cr${}_2$o${}_3$ effect on the structure, optical, and radiation shielding properties of na${}_2$b${}_4$o${}_7$-sio${}_2$-cao-cr${}_2$o${}_3$ glasses

65Na${}_2$B${}_4$O${}_7$-25SiO${}_2$-(10-x) CaO-x Cr${}_2$O${}_3$ x = (0 $\le$ x $\le$ 5 mol.%) glass system was synthesized and optical, structural, and radiation shielding characteristics are examined. The glass density increased as Cr${}_2$O${}_3$ was added, while the molar volume decreased. FT-IR bands are correlated with the vibrations of BO${}_3$ and BO${}_4$. Cr${}^{3+}$ appears to convert BO${}_3$ into BO${}_4$, according to preliminary FT-IR results. E${}_{opt}$ values are in the range of 2.57-3.31 eV. Increases in the E${}_{opt}$ can be linked to density and N${}_4$ variation. (Zeq) increased then decreased as the incident photon energy increased with the replacement of CaO by Cr${}_2$O${}_3$. $\sum$ R enhances as the Cr${}_2$O${}_3$ content of the glasses increases. G 5 is a better absorber of fast neutron when the FNRC of glass samples is compared. For neutron attenuation applications, the glass sample G 5 is the best option.