Stoichiometric and nonstoichiometric cadmium gallate (gallium-rich) samples have been synthesized by a modified epoxide gel method. Cubic spinel arrangement was inferred for stoichiometric and gallium-rich compositions from powder X-ray diffraction analysis. Complete structural analysis employing Raman spectroscopy has been carried out to find the intricate differences between these two samples. Additional evidence for the cubic symmetry and elemental ratio of these samples has been gathered using microscopy techniques and energy-dispersive X-ray analysis. Li+ substitution for Cd2+ in gallium-rich spinel was examined, and up to 60 mol % of Cd2+ could be substituted with Li+, retaining the spinel arrangement. The introduction of lithium led to a decrease in cubic lattice parameter. Changes in the vibration modes upon lithium substitution were analyzed by Fourier transform infrared and Raman spectral measurements. The band gap value was found to increase with increase in lithium content, indicative of the B...