Electronic excitation and electric field as switching mechanism for a single-molecule switch

DFT calculations show that a combination of an electric field and electronic excitation is promising mechanism to force molecular switch based on amino-imino tautomerisation into one its two states. By calculating the effect in direction moving hydrogen shape barrier ground low-lying excited states previously proposed switches consisting 5- 7-membered rings with adjacent amino imino groups, we demonstrate fields photons experimentally accessible ranges introduce sufficient asymmetry push desired configuration. Excitation inverted order preferred geometry allows reversible switching without reversal field.