Evolution of the ionisation energy with the stepwise growth of chiral clusters of [4]helicene oleh Sérgio R. Domingos, Denis S. Tikhonov, Amanda L. Steber, Patrick Eschenbach, Sebastien Gruet, Helgi R. Hrodmarsson, Kévin Martin, Gustavo A. Garcia, Laurent Nahon, Johannes Neugebauer, Narcis Avarvari, Melanie Schnell