New lanthanide hybrid as clustered infinite nanotunnel with 3D Ln-O-Ln framework and (3,4)-connected net

A series of new lanthanide hybrids [Ln(3)(mu-OH)(4) (2,5-pydc)(2,5-Hpydc)(3)(H2O)(4)](n) (Ln = Gd (1), Dy (2), Er (3), Eu (4), Sm (5), Yb (6), Y (7); 2,5-pydc=pyridine-2,5-dicarboxylate), as clustered lanthanide oxide ring tunnels with helical dodecahedral chains and fully 3D Ln-O-Ln connectivity, has been hydrothermally synthesized and characterized. The inorganic skeleton of the hybrid can be specified by the Schlafli symbol (6(2)10)(2) (6(4)10(2)) as a single 3D (3,4)-connected net. The luminescence properties have been studied, and the results showed that the Dy(III) (2) and Eu(III) (4) complexes exhibited sensitized luminescence in the visible region. Variable-temperature magnetic susceptibility measurements of 1-6 showed that the complexes 1-3 are nearly paramagnets, whereas the depopulation of the Stark levels in complexes 4-6 leads to a continuous decrease in mu(eff) when the sample is cooled from 300 to 2 K.