We have investigated the optical properties of Ni2+ cations in aqueous and alcohol solutions of NiCl2 · 6H2O at room temperature. We measured the absorption spectra of these two types of solutions in the spectral region 395-795 nm. The Racah’s parameters and the exchange integrals of the aqueous complex [Ni(H2O)6]2+ have been calculated. The parameters Dq, Dt and Ds are also calculated on the basis of our experimental data. The parameters δσ and δπ, connected with the symmetry of the complex, are determined.