Synthesis, Crystal Structure and Luminescent Properties of a Nd(III) Complex Constructed from 2-Pyridyl-4,5-imidazoledicarboxylic Acid

A new Nd(III) coordination polymer [Nd(pidc)(H2O)(4)]center dot pidc(-)center dot 7H(2)O (1, pidc(2-) = 2-Pyridyl-4,5-imidazoledicarboxylate) has been synthesized by solvothermal reaction at 120 degrees C and structurally characterized. The complex belongs to triclinic, space group P (1) over bar with a = 9.022(2), b = 13.731(3), c = 13.782(3) angstrom, alpha = 70.87(3), beta = 71.71(3), gamma = 71.71(3), V = 1488.6(7) angstrom(3), Z = 2, D-c = 1.798 g/cm(3), S = 1.04, mu = 1.839 mm(-1), F(000) = 814, M-r = 805.76, R-int = 0.081 and wR = 0.1644 for 5242 observed reflections (I > 2 sigma(I)). Each Nd3+ ion is nine-coordinated by five O atoms from three pidc ligands, and four O atoms from lattice water molecules. Each pidc is coordinated to three Nd3+ ions with a mu(3)-kappa O:kappa O':kappa O '',kappa O'''-mu(2) coordination mode into 1D chains, which can be further built into a 3D framework through intermolecular N-H center dot center dot center dot O and O-H center dot center dot center dot O hydrogen bonds. Photoluminescent studies have shown that 1 exhibits emission at 439 nm (lambda(ex) = 395 nm).