Synthesis and structural characterization of lanthanide metal complexes by 2-fluorobenzoic acid with 2,2:6,2"-terpyridine, and their fluorescence properties

Three new lanthanide complexes were synthesized by conventional solution synthesis at room temperature with the formula of [Ln(2-FBA)(2)(terpy)(NO3)(H2O)].(terpy).H2O(Ln= Dy(1)), [Ln(2-FBA)(3) terpy](2).2(2FHBA).2H O-2(Ln=Pr(2),Tb(3)), (2-FBA=2-fuorobenzoate, terpy=2,2' :6',2 ''-terpyridine). The complexes were characterized by elemental analysis, X-ray single crystal diffraction and infrared spectroscopy. The coordination number of complexes 1-3 is 9, showing a muffin geometry. Complex 1 is mononuclear, crystallized in the monoclinic system and space group P2(1)/c. Complexes 2 and 3 are binuclear molecules of isomorphous, and their adjacent structural units form 1D chain and 2D sheets structure through CH center dot center dot center dot F hydrogen bonding and pi-pi stacking interactions. In addition, the solid state fluorescence spectra of complexes 1 and 3 were measured. The test shows that complex 3 emits strong green light. The thermal decomposition mechanism of the complexes was studied by synchronous thermal analyzer infrared spectroscopy TG-DSC/FTIR and the 3D stacked plots of the escape gases were analyzed. (C) 2021 Elsevier B.V. All rights reserved.