Crystal structures, DFT and fluorimetric study of a dual nature Schiff base chemosensor for detection of Cu2+ and Ce4+ ions in aqueous media

A dual nature Schiff base chemosensor3,5-bis(((2-hydroxynaphthalen-1-yl)methylene)amino) benzoic acid (3,5-BHNMABA) was synthesized and characterized by single crystal X-rays diffraction. The interaction of the photophysical properties of the ligand with various metal ions (aqueous) was extensively analyzed through fluorescence spectrophotometry. EHOMO-ELUMO energy gap and molecular electrostatic potential study was performed by DFT calculations. Strong quenching in emission was observed for Cu2+ and Ce4+ ions. Binding ratio between Cu2+/Ce4+ ions with ligand was calculated by Job's plot. LOD and LOQ were calculated as 7.92 x 10-6 M and 2.40 x 10-5 M for Cu2+ ions whereas 5.9 x 10-6 M and 1.97 x 10-5 M for Ce4+ ions.