\(\:{\text{N}\text{i}}^{2+}\) ions bearing aluminoborate glass host are promising materials in the optics realm. Herein, a glass set was designed and prepared using melt-quenching method, in which the aluminum oxide was added to modify the borate structure. The article investigates the structure, optical, magnetic and optical non-linear properties of glass. The structure was investigated by X-ray diffraction, energy dispersive x-ray, mass density, and infrared spectra. The addition of aluminum oxide enhanced the structure by enhancing the amorphousness, establishing distinguished structural units in the glassy host and increasing the mass density. Optically, the absorption spectra revealed the occupancy of divalent nickel activators in octahedral sites. Ligand field calculations confirmed the role of aluminum ions in strengthening the interactions between activator ions and their ligand, enhancing the covalent bonding nature between them. In addition, the aluminum addition creates more non-bridging bonds that decreases the glass optical band gap. Moreover, the increased density and polarization of aluminum ions increased the overall non-linear optical properties of glass set. Electron spin resonance results agreed with infrared and optical data, with more domination of octahedral sites of nickel ions, as modifiers, in glass network. These findings encourage the use of current glass set in optical applications.
