Two three-dimensional lanthanide frameworks exhibiting luminescence increases upon dehydration and novel water layer involving in situ decarboxylation.

Two three-dimensional polymeric Tb(III) and Yb(III) frameworks, namely, {[Tb3(Hptc)(ptc)(pdc)(H2O)6]·2H2O}n (1) and {[Yb2(ptc)(ox)(H2O)5]·7H2O}n (2) (H4ptc = pyridine-2,3,5,6-tetracarboxylic acid, H2pdc = pyridine-3,5-dicarboxylic acid, ox = oxalate), have been synthesized by a hydrothermal method and characterized by infrared spectra, elemental analysis, powder X-ray diffraction, thermogravimetric analysis, and single-crystal X-ray diffraction. Framework 1 shows an interesting three-dimensional (8,8)-connected net with a Schläfli symbol of (3(3)·4(18)·5(5)·6(2))2(3(6)·4(14)·5(7)·6), while 2 exhibits an unusual (4,8)-connected sqc21 net with a Schläfli symbol of (3(2)·4(2)·5(2))(3(4)·4(8)·5(12)·6(4)). Luminescence studies of 1 reveal that the luminescence intensity increases when the framework is dehydrated.