A series of synthesized small organic molecules based on the 4H-1,2,6-thiadiazine moiety are studied using electrochemistry, to probe their potential as comonomer building blocks for solar-absorbing polymers for organic solar cells. This is the first instance of an electrochemical report for this family of heterocycles. Structure-physical property relationships are identified that can guide future synthetic efforts. Parameters that can influence the properties of the final copolymer such as the choice of electron donor comonomer and the energy level of the fullerene adduct acceptor are factored-in and discussed and the thiadiazines that can meet the requirements are singled-out. (C) 2013 Elsevier Ltd. All rights reserved.