caa a22 4500 60548760X CHVBK 20210128100451.0 cr unu---uuuuu 210128e20151201xx s 000 0 eng 10.1007/s00214-015-1750-3 doi (NATIONALLICENCE)springer-10.1007/s00214-015-1750-3 Helical molecular redox actuators with pancake bonds? [Elektronische Daten] [Pierre Beaujean, Miklos Kertesz] In an attempt to design molecular electromechanical actuators with large deformation response, we present here three helicene-like compounds, which offer significant strain above 5% due to two-electron charge transfer (CT). The shrinking induced by CT is a quantum mechanical orbital effect. A good π-π overlap across the helical pitch is critical for this type of actuation. The relevant overlap refers to frontier orbitals that are involved in the CT, and it has some features common with π-π stacking pancake bonds; however, these molecules do not represent all aspects of typical pancake bonding. This overlap is accompanied by a change in the bond length alternation pattern indicating significant change in π-conjugation. Additionally, two further helicene-like molecules included in this study also indicate large electromechanical actuation, but a simple orbital interpretation is not available in those cases. Springer-Verlag Berlin Heidelberg, 2015 Molecular actuators nationallicence Charge transfer nationallicence Helical structure nationallicence π-π Overlap nationallicence Density functional theory computations nationallicence Beaujean Pierre Laboratoire de Chimie Théorique, Unité de Chimie Physique Théorique et Structurale, Université de Namur, rue de Bruxelles 61, 5000, Namur, Belgium aut Kertesz Miklos Department of Chemistry and Institute of Soft Matter, Georgetown University, 37th and O Streets, NW, 20057-1227, Washington, DC, USA aut Theoretical Chemistry Accounts Springer Berlin Heidelberg 134/12(2015-12-01), 1-10 1432-881X 134:12<1 2015 134 214 https://doi.org/10.1007/s00214-015-1750-3 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s00214-015-1750-3 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Beaujean Pierre Laboratoire de Chimie Théorique, Unité de Chimie Physique Théorique et Structurale, Université de Namur, rue de Bruxelles 61, 5000, Namur, Belgium aut NATIONALLICENCE 700 1- Kertesz Miklos Department of Chemistry and Institute of Soft Matter, Georgetown University, 37th and O Streets, NW, 20057-1227, Washington, DC, USA aut NATIONALLICENCE 773 0- Theoretical Chemistry Accounts Springer Berlin Heidelberg 134/12(2015-12-01), 1-10 1432-881X 134:12<1 2015 134 214