Variable Dimensionality of Europium(III) and Terbium(III) Coordination Compounds with a Flexible Hexacarboxylate Ligand

A reaction between 4,4′,4″-(benzene-1,3,5-triyltris(oxy))triphthalic acid (H(6)L) and lanthanide(III) nitrates (Ln = Eu(3+), Tb(3+)) in water under the same conditions gave a molecular coordination compound [Tb(H(4.5)L)(2)(H(2)O)(5)]∙6H(2)O in the case of terbium(III) and a one-dimensional linear coordination polymer {[Eu(2)(H(3)L)(2)(H(2)O)(6)]∙8H(2)O}(n) in the case of europium(III). The crystal structures of both compounds were established by single-crystal X-ray diffraction, and they were further characterized by powder X-ray diffraction, thermogravimetric analysis and infrared spectroscopy. The compounds demonstrated characteristic lanthanide-centered photoluminescence. The lanthanide-dependent dimensionality of the synthesized compounds, which are the first examples of the coordination compounds of hexacarboxylic acid H(6)L demonstrates its potential as a linker for new coordination polymers.