An intramolecular charge transfer (ICT) based chemosensor for silver ion using 4-methoxy-N-((thiophen-2-yl)methyl)benzenamine.

4-Methoxy-N-((thiophen-2-yl)methyl)benzenamine was found to be a highly selective chemosensor for Ag(+) ion in methanol-water (1 : 1 v/v) mixture over other metal ions such as Na(+), K(+), Li(+), Cu(+), Ba(2+), Cd(2+), Co(2+), Cu(2+), Fe(2+), Hg(2+), Mn(2+), Ni(2+), Pb(2+) and Zn(2+) with a limit of detection (LOD) is 5.0 × 10(-6) mol L(-1). Upon binding to Ag(+) ion, a strong fluorescent enhancement is observed which is attributed to an increase in intramolecular charge transfer (ICT). The proposed mechanism is strongly supported by TD-DFT calculations.