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The optical properties of Pr3+ activated LuCl3 and LuBr3 under intra-ionic 4f2rarr 4f1 5d1 and band gap (lambdaex = 193 nm; X-ray) excitations have been evaluated. The luminescence of Pr 3+ in these hosts is found to be strongly dependent on the excitation energy: for energies less than the absorption edge of the host, the luminescence is dominated by the 4f1 5d1 rarr 4f2 interconfigurational optical transitions. When luminescence is excited by photons with energies corresponding to the absorption edge or the band gap of the host, the emission spectrum is dominated by the intraconfigurational 4f2rarr 4f2 optical transitions, which emanate from the Pr3+ 3PJ states. A model to account for the dependence of the emission behavior of Pr3+ ion on the excitation energy is presented.