A molecular half-adder and half-subtractor based on pyrylium

A very simple molecular cation, 4-(4-dimethylaminophenyl)-2,6-diphenylpyrylium, has been demonstrated to have a function of molecular half-adder and half-subtractor according to the detectable spectroscopic changes of the molecular system in response to the inputs of acid and base. Distinct algebraic operations can be performed in this reconfigurable molecular logic system.