A fluorescent bischromophoric dyad combining anthracene and naphthalic anhydride units has been synthesized and characterized. The dyad shows a FRET mediated emission signal at∼ 535 nm when excited at λex.= 380/360 nm, with efficient energy transfer efficiency (ET= 93%) and quantum yield (Φ= 0.155). Upon interaction with F− and Hg2+ ions selectively, a diminished (switched-Off) FRET signal is observed and the naked-eye ...