Synthesis, crystal structure and magnetic properties of two 3-D gadolinium complexes

Abstract

Two new gadolinium coordination polymers, Gd(tci)(H₂O)]·DMF·2H₂O (1) and [Gd(bci)(H₂O)]·2H₂O(2) (H₃tci = tri(2-carboxyethyl)isocyanurate, H₃bci = bis(2-carboxyethyl)isocyanurate), have been synthesized under solvothermal conditions by the reaction of gadolinium nitrate and H₃tci or H₃bci with presence of DMF and H₂O. 1 and 2 feature an interesting 3D metal–organic framework which contains infinite linear Gd-(µ-O)₂-Gd chains in the structures. The carboxylate groups bridge two Gd(III) centers in µ₂-carboxylato-κ¹O: κ¹O′ and µ₂O;κ²O,O′ patterns for 1 and µ₂O;κ²O,O′ fashion for 2. The magnetic studies indicate that there exist antiferromagnetic interactions in 1 and ferromagnetic interactions in 2. The best fittings to the experimental magnetic susceptibilities gave J = −0.015 cm⁻¹, g = 1.98 for 1 and J = 0.055 cm⁻¹, g = 1.98 for 2.