Synthesis, structures, photoluminescence and magnetic properties of three dinuclear lanthanide(III) complexes derived from 4-fluorophenylselenoacetic acid

Three novel dinuclear lanthanide(III) complexes [Ln(2)L(6)(phen)(2)] (Ln=Eu-III (1), Tb-III (2), Dy (III) (3)), derived from 4-fluorophenylselenoacetic acid and 1,10-phenanthroline, have been synthesized and characterized by elemental analysis, IR, TGA, powder X-ray diffraction and single-crystal X-ray diffraction analysis. Single crystal X-ray diffraction reveal they are isostructural and crystallize in the monoclinic crystal system, space group P2(1)/c. The investigations on luminescent properties of Eu(III) complex 1 and Tb(III) complex 2 exhibit the characteristic emissions of Eu-III (D-5(0)-> F-7(0-4)) and Tb-III (D-5(4)-> F-7(6-3)), and the corresponding luminescent lifetimes are 1.52 and 1.10 ms, respectively. Temperature-dependent photoluminescence studies show the emission intensities and lifetimes for both complexes decrease upon increasing temperature, which indicates complexes 1 and 2 have the potential for sensing temperature. The magnetic studies reveal that Dy(III) complex 3 exhibits weak antiferromagnetic interactions and slow magnetic relaxation behavior.

Automated summary

Three novel dinuclear lanthanide(III) complexes were synthesized and characterized. Eu(III) and Tb(III) complexes exhibited characteristic luminescent properties and potential for temperature sensing, while Dy(III) complex showed weak antiferromagnetic interactions and slow magnetic relaxation behavior.