Solar energy storage reactions involving polynuclear rhodium isocyanide complexes. Flash photolysis studies in aqueous sulfuric acid solutions

Results of flash photolysis studies of the complexes Rh/sub 2/(bridge)/sub 4//sup 2 +/ where bridge = 1,3 diisocyanopropane are reported. The decay of the complex was found to obey second-order kinetics, and the product of the charges of the reactants was found to be 8.1. This result suggests that the complex is present in aqueous solutions as a tetranuclear species. The results of the flash photolysis studies can be explained by assuming that the complex is )Rh/sub 2/(bridge)/sub 4//sup 3 +/)/sub n/ where n = 2. Irradiation of solutions of the complex in concentrated halogen acids led to complete conversion to the halogen form of the bridge complex and hydrogen.