[en] The liquid aprotic system SOCl₂-GaCl₃-UO₂Cl₂ is synthesized. The absorption and luminescence (at 300 and 77 K) spectra are studied. The uranyl luminescence quenching time is determined. Photochemical reduction of UO₂²⁺ to U⁴⁺ occurs on irradiation of SOCl₂-GaCl₃-UO₂Cl₂ solutions by light (λ < 500 nm). This produces unstable luminescent-spectral properties in the studied system. The reduction does not occur under conditions excluding the incident light. Since the laser properties of the SOCl₂-GaCl₃-NdCl₃ system are well known, the last feature provides hope that stable laser luminophores coactivated by ²³⁸U, ²³⁵U, and Nd can be prepared and that Nd can be excited by products of nuclear reactions