Synthesis and Characterization of Ln(III) Complexes and its Luminescence Properties.

Hexadentate ligand L and its Ln(3+) complexes EuLCl3 (1), TbLCl3 (2), SmLCl3 (3) are synthesised. All these complexes are well characterized for their photophysical properties such as luminescence lifetime decay(τ) and overall quantum yield(Φ). These complexes being water soluble, depicts their intense metal centred luminescence. Effect of pH on these complexes suggest that their emission intensities are stable in the pH range 4-9 and show their compatibility to function in the physiological pH. Graphical Abstract Normalized emisson spectra of complex 1, 2 and 3 (1x10(-5)M) in HEPES Buffer at pH 7.4 (λexc=276nm).