Intermolecular and intramolecular logic gates

Logic circuits operating on different molecules or on different parts of the same molecule can be connected. As an example, a circuit known as a full adder is described. It is made up of two circuits, a half adder on a donor (rhodamine 6G) and another half adder on an acceptor (azulene). The signal, (an intermediate sum), is moved from donor to acceptor by electronic energy transfer. The concatenated logic arrangement is described, and potential applications using other bichromophoric molecules are outlined. Polychromophoric molecules will allow a fanout operation.