The ionic radii of Al3+ (0.54 Å) in BaAl glass allow it to fit easily in either tetrahedral or octahedral sites in an oxygen structure. If it is connected as tetrahedrally it works as a network former otherwise it acts as modifier. It is well reported in the literature, that less than 5 mol% Al2O3 in glass composition acts as glass former and above that it acts as modifier. Al3+ along with Ba2+ enters into the glass network and form hexacelsian phase as shown in