Unusual photoluminescence properties of the 3D mixed-lanthanide-organic frameworks induced by dimeric structures: a theoretical and experimental approach

The present work describes a complementary experimental and theoretical investigation of the spectroscopic properties of the four isostructural 3D Ln-MOFs (wherein PDC = pyrazole-3,5-dicarboxylate, [La-2(PDC)(3)(H2O)(4)]center dot 2H(2)O (1), [(La0.9Eu0.1)(2)(PDC)(3)(H2O)(4)]center dot 2H(2)O (2), [(La0.9Tb0.1) 2(PDC) 3(H2O) 4]center dot 2H(2)O (3) and [(La0.9Eu0.5Tb0.5) 2(PDC) 3(H2O) 4]center dot 2H(2)O (4)). The experimental data and theoretical calculations show that the singular photophysical properties presented by these Ln-MOFs are induced by strong interaction between the Ln3+ ions.