Maximizing the solar energy storage of the four substituted norbornadiene-quadricyclane system: DFT calculations

The purpose of this research is to study the solar energy storage in norbornadiene (1)/quadricyclane (2) system by four direct attachments of substituents at two carbon atoms on both sides of the double bonds C2=C3 and C5=C6 in 1 X and 2 X; calculating the relative energies at B3LYP/6-311++G** level of theory. The solar energy storage of four electron donating substituents, (push-push effect), X (X =–NH2,–OH) and four electron withdrawing substituents, (pull-pull effect) X (X =–CO2H,–CONH2,–NO2 and CN) were examined. The solar absorption bands were calculated for 1 X. The DFT calculations reveal that the bands were shifted to the visible spectrum region when the electron withdrawing substituents were used rather than the electron donating substituents.