Syntheses, Structures and Magnetic Properties of Rare Earth Metal‐Organic Frameworks (REMOFs) Templated by Silicotungstic Heteropolyanion

Abstract Two new rare earth metal‐organic frameworks (REMOFs) [Ln(pydc)(H 2 O) 4 ] 4 SiW 12 O 40 ⋅ x H 2 O (Ln= Pr ( 1 ), Nd ( 2 ) ; pydc=2,6‐pyridine dicarboxylic acid; x = 4.51, 4.64) have been hydrothermally synthesized. The compounds are isostructural, and each possesses a 3D zeolite‐like cationic framework with the GIS topology. The typical Keggin‐anions [SiW 12 O 40 ] 4− are located in the nano‐sized cages through electrostatic interaction and strong hydrogen bonding interaction. Our results indicate that Keggin‐type silicotungstic heteropolyanion is an efficient template for the construction and stabilization of 3D REMOFs. Magnetic measurements of compound 2 reveal the presence of a small anisotropy of the Nd III ions. The thermal and solid‐state fluorluminescent properties of both compounds have been investigated as well.