CRYSTAL STRUCTURE, FLUORESCENCE SPECTROSCOPY, AND ELECTROCHEMICAL PROPERTY OF TWO NEODYMIUM COORDINATION POLYMERS WITH PHENOXY ACIDS

摘要

Two nine-coordination coordination polymers of neodymium, [Nd_2(p-C_8H_4O_4)(o-C_8H_4O_4)_2 · 4H_2O]_n (I), [Nd_2(C_(10)H_4O_8)(C_(10)H_2O_8) ? 2H_2O]_n (II), have been prepared by hydrothermal reaction of Nd(NO_3)_3 ? 6H_2O with terephthalic acid and phthalic acid, or benzenetetracarboxylic anhydride and determined by means of IR, UV, fluorescence, TG-DTA, cyclic voltammetry (CV) and X-ray single-crystal diffraction methods (CIF files CCDC nos. 1006206 (I), 979309 (II)). Yellow-green luminescence could been observed at 391 nm (λ_(ex) = = 305 nm) for complex I and 370 nm (λ_(ex) = 331 nm) for the complex II. The emission of complexes I and II may be due to the π* → n transition, which may be assigned to the ligand-to-metal charge-transfer bands. Compared with complex II, the complex I exhibits a stronger fluorescence intensity for the different coordinated environment. Cyclic voltammetric measurement of the two compounds reveal that the compounds both have a couple of irreversible redox peak, indicating that the two polymers were both corresponded to the unusual Nd(III)/Nd(V).