A single chemosensor with combined ionophore/fluorophore moieties acting as a fluorescent “Off-On” Zn2+ sensor and a colorimetric sensor for Cu2+: Experimental, logic gate behavior and TD-DFT calculations

•Hqpzc operates as a combined ionophore/fluorophore sensor for Zn2+ in acetonitrile.•The sensing of Zn2+ is based on the CHEF mechanism; no interference from other Mn+ ions.•Hqpzc also acts as a specific colorimetric sensor for Cu2+ in acetonitrile.•An INHIBIT type logic gate is constructed with Zn2+ and SCN− as chemical inputs.•DFT/TD-DFT calculations support the experimental observations.