Synthesis and Characterization of a Novel Lanthanide Complex with Photoluminescent and Semiconductive Properties

A novel lanthanide complex [La(2,5-PA)(2,5-HPA)(H 2 O) 2 ] n · n H 2 O (I) (2,5-H 2 PA = 2,5-pyridinedicarboxylic acid) was synthesized by a hydrothermal reaction and structurally characterized by singlecrystal X-ray diffraction (СIF file CCDC no. 1570808). Complex I is characteristic of a two-dimensional (2D) layered structure with the La 3 + ion coordinating with seven oxygen atoms and two nitrogen atoms to yield a slightly distorted monocapped square antiprism. The [La(2,5-PA)(2,5-HPA)(H 2 O) 2 ] n layers and lattice water molecules interlink together through hydrogen bonding interactions to give a three-dimensional (3D) supramolecular framework. Photoluminescence measurements under room temperature with solidstate samples show that it displays an emission in the green region of the light spectrum. Solid-state UV-Vis spectrum conducted with solid-state samples reveals the existence of a wide optical band gap of 3.57 eV.