Some recent structural studies [11] show the presence of BiO6 octahedra as the main structural unit in the Bi2O3-based glasses containing Li+ions. Li+ions occupy the interstices to compensate the excess negative charge of BiO6 octahedra in low-alkali-content glasses, whereas with high alkali content the replacement of some relatively strong Bi–O bonds by weak Li+–O_ bonds takes place resulting in a decrease in the mean bond strength and connectivity in the glass network which are responsible for more open structure. B2O3 is a glass forming oxide whereas Bi2O3 is a conditional glass former and the presence of these two in the glass matrix results to a low rate of crystallization and moisture resistant stable glasses are formed. Boron atoms in these glasses are both three and four- coordinated and are generally designated as B3 and B4 units [12–19]. B4 units give rise to tetrahedral network features of the glass.