Two isostructural fluorinated metal-organic frameworks with rare rod-packing architecture: syntheses, structures and luminescent properties

Abstract

Abstract Two isostructural fluorinated metal-organic frameworks, formulated as [M 2(Fbix)(1,4-NDC)2] n (M=Cd for 1 and Mn for 2), were synthesized by employing 1,4-naphthalenedicarboxylic acid (1,4-H2NDC) and the flexible fluorinated ligand 2,3,5,6-tetrafluoro-1,4-bis(imidazole-1-yl-methyl)benzene (Fbix) under hydrothermal conditions. Their structures were determined by single-crystal X-ray diffraction and further characterized by infrared spectroscopy, powder X-ray diffraction, and thermogravimetric analyses. Structure analyses have revealed that compounds 1 and 2 show an unusual hex net based on infinite rod-shaped secondary building units. The solid-state fluorescence spectra of 1 and 2 were measured and indicate a ligand-based emission for both complexes.