Dimer Radical Anions of Polyfluoroarenes. Two More to a Small Family

Dimer Radical Anions of Polyfluoroarenes. Two More to a Small Family Full article

Journal

Journal of Physical Chemistry A
ISSN: 1089-5639

Output data

Year: 2019, Volume: 123, Number: 51, Pages: 10968-10975 Pages count : 8 DOI: 10.1021/acs.jpca.9b09906

Authors

Beregovaya Irina V ¹ , Shchegoleva Lyudmila N. ¹ , Ovchinnikov Dmitry A. ^2,3 , Blinkova Svetlana V. ² , Borovkov Vsevolod I. ² , Andreev Rodion V. ¹ , Bagryansky Victor A. ² , Molin Yuri N. ²

Affiliations

1	N. N. Vorozhtsov Novosibirsk Institute of Organic Chemistry, SB RAS, 9 Ac. Lavrentiev Avenue, Novosibirsk 630090, Russia
2	Voevodsky Institute of Chemical Kinetics and Combustion, SB RAS, 3 Institutskaya str., Novosibirsk 630090, Russia
3	Novosibirsk State University, 2 Pirogova str., Novosibirsk 630090, Russia

While there is a body of experimental data concerning dimers formed by an aromatic molecule and its radical cation, information on the corresponding dimer radical anions (DRAs) is scarce. In this work, evidence for the formation of the DRAs of decafluorobiphenyl and 4-aminononafluorobiphenyl has been obtained by the optically detected electron paramagnetic resonance and the time-resolved magnetic field effect techniques. Theoretical investigation (DFT B3LYP-D3/6-31+G*) of these DRAs and the DRAs of octafluoronaphtalene and 1,2,4,5-tetrafluorobenzene previously detected by Werst has been undertaken to gain greater insight into the structure of the polyfluoroarene DRAs. Without substituents different from a fluorine atom, an extra electron is evenly delocalized over two fragments; the bonding interaction is pi stacking. On the potential energy surfaces (PES), there are two minima of nearly equal energy corresponding to the structures of perfect and parallel displaced sandwiches. Such a PES structure is due to a conical intersection between two electronic states of different symmetry. The DRA of 4-aminononafluorobiphenyl is an ion-molecular associate stabilized by electrostatic interactions involving NH2 groups. The complex cyclic structure of the PES of this DRA suits the successive electron transfers between the dimer fragments. The calculated hyperfine coupling constants averaged over the PES minima agree well with the experimental ones.

Beregovaya I.V. , Shchegoleva L.N. , Ovchinnikov D.A. , Blinkova S.V. , Borovkov V.I. , Andreev R.V. , Bagryansky V.A. , Molin Y.N.
Dimer Radical Anions of Polyfluoroarenes. Two More to a Small Family
Journal of Physical Chemistry A. 2019. V.123. N51. P.10968-10975. DOI: 10.1021/acs.jpca.9b09906 WOS Scopus РИНЦ

Submitted:	Aug 22, 2019
Accepted:	Nov 25, 2019
Published online:	Nov 26, 2019
Published print:	Dec 26, 2019

Web of science	WOS:000505631100013
Scopus	2-s2.0-85076635237
Elibrary	43215515
OpenAlex	W2990568747