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 ( 5 D 0 ! 7 F 0-4 ) and Tb III ( 5 D 4 ! 7 F 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.