The electronic and molecular structures of a family of oligothienylenevinylenes for organic solar cells are studied by means of UV/Vis, fluorescence and Raman spectroscopy, aided by quantum chemical calculations. By using different anchoring groups, the alteration of the electronic properties upon inserting electron-withdrawing groups into different positions on the oligothienylenevinylene backbone is determined. In addition, a thorough study of the photophysical properties is carried out to understand their potential use in optoelectronic devices. The charge defect of one of these systems is analysed to elucidate the possible charge carriers photogenerated during device operation.