C22H46: the smallest open 3(1)-knotted alkane by computer-aided design.
The program MolKnot [Chem. Phys. Lett. 433 (2007) 422-426] has been used in order to detect the smallest ever-reported alkane configured to an open-knotted shape with three crossings (3(1)). High level ab initio calculations support our findings that 22 carbon atoms are enough to create a knotted polyethylene strand with open ends. These tight open molecular knots exhibit unusually distorted geometric characteristics as multiple extended CC bonds (maximum bond length approximately 1.70A) and several large CCC bond angles (maximum bond angle approximately 145 degrees ). The energy decomposition shows that the strain mainly affects the valence angles of the entangled structure. We observed that this 22-knotted carbon atoms' region remained almost intact as a part of alkanes with longer chain lengths.
Krinas
Christos S
CS
Department of Chemistry, Section of Physical Chemistry, University of Ioannina, Panepistimioupoli Dourouti, Ioannina 45110, Greece.
Demetropoulos
Ioannis N
IN
D000473:Alkanes / Q000737:chemistry*; D003198:Computer Simulation; D017076:Computer-Aided Design; D008958:Models, Molecular; D015394:Molecular Structure; D020959:Polyethylene / Q000737:chemistry*; D012984:Software
D000473:Alkanes; D020959:Polyethylene