The absorption spectrum for three types of metal ions in different concentrations has been studying experimentally and theoretically. The examination model is by Gaius model in order to find the best fitting curve and the equation controlled with this behavior. The three metal ions are (Copper chloride Cu+2, Iron chloride Fe+3, and Cobalt chloride Co+2) with different concentrations (10-4, 10-5, 10-6, 10-7) gm/m3. The spectroscopic study included UV-visible and fluorescence spectrum for all different concentrations sample. The results refer to several peaks that appear from the absorption spectrum in the high concentration of all metal ions solution. The multiple absorption peaks continued even at the lowest concentration in the iron ion solution. Fluorescence spectrum shows intensive stimulating of the radiation strength was perceived in the manifestation of Cu+2, Co+2 and Fe+3. From modeling investigation, there are converge between experimental and theoretical results of the fluorescence spectrum for metal ions. Furthermore, identity and convergence which defined as (r2), are on average (0.995).
