Intermolecular charge-transfer (CT) complexes between dichloronaphthoquinone (DCN) as acceptor and amine derivatives as donors such as ethylamine, diethyl-amine, triethyl-amine were investigated using spectroscopic techniques. The colorimetric signaling of CT complex from the point of view of their energy levels was carried out by theory calculation. The CT complexes were highly colored with ethylamine, diethyl-amine, triethyl-amine sensing giving rise to a colorless to yellow, red, and blue, respectively. A simple "OR" logic operation was successfully realized by ethylamine, diethyl-amine as input signals. Due to the dependence of the CT complexes absorption intensity of added ethylamine and diethyl-amine, it is possible to mimic the function of the truth table of an "OR" gate.