Europium(III) and terbium(III) trans-2-butenoates: syntheses, crystal structures, and properties

Abstract

Homometallic europium(III) and terbium(III) trans-2-butenoate polymers, chemical formulas [{Eu-3(MeCH=CHCO2)(9)(H2O)(4)}.H2O-EtOH](n) (1) and [{Tb(MeCH=CHCO2)(3)(H2O)}.MeCH=CHCO2H](n) (2) and their dimeric 1,10-phenanthroline derivatives [Ln(2)(MeCH=CHCO2)(6)(phen)(2)].2H(2)O, with Ln = Eu (3) and Tb (4), were prepared and characterized by single-crystal X-ray diffraction. The coordination polymers 1 and 2 adopt different carboxylate-bridged infinite chain structures. While the europium compound I shows three independent europium centers linked to each other by three different types and number of carboxylate bridges, the terbium polymer 2 shows one independent metal center bridged by the same type of double carboxylates along the chains. Compounds 3 and 4 are isomorphous dinuclear structures with quadruply bridged carboxylate groups, two in the eta(1):eta(1):mu(2) and two in the eta(2):eta(1):mu(2) modes. The magnetic and photophysical behaviors of the four compounds are reported in the solid state.