In chemistry, charge-transfer (CT) complex, or electron donor-acceptor complex, describes a type of supramolecular assembly of two or more molecules or ions.  The assembly consists of two molecules that self-attract through electrostatic forces, i.e., one has at least partial negative charge and the partner has partial positive charge, referred to respectively as the electron acceptor and electron donor.  In some cases, the degree of charge transfer is "complete", such that the CT complex can be classified as a salt.  In other cases, the charge-transfer association is weak, and the interaction can be disrupted easily by polar solvents.