8-hydroxyquinoline (oxine) and uranyl acetate react in the solid state in 1∶3 stoichiometry to give UO2(C9H6NO)2·C9H6NOH. This reaction is diffusion controlled with an activation energy of 44.4 kJ mol−1. The reaction occurs by the surface migration of 8-hydroxyquinoline, which penetrates the product lattice to react with uranyl acetate. The isothermal decomposition of the solution phase product UO2Q2·HQ (Q=C9H6NO) obeys the Prout-Tompkins equation with an energy of activation of 53.3 kJ mol−1.