A dual-responsive "turn-on" bifunctional receptor: a chemosensor for Fe3+ and chemodosimeter for Hg2+.

Synthesis of L1-L3, their thorough characterization by spectral as well as structural studies and use in selective photochemical detection of Fe3+ and Hg2+ at ppb level have been described. Notably, these exhibit bifunctional behaviour toward Fe3+ (CHEF) and Hg2+ (chemodosimetric) which has been unequivocally established by various studies.