n-Dopants Based on Dimers of Benzimidazoline Radicals: Structures and Mechanism of Redox Reactions
Naab, Benjamin D.
Jucov, Evgheni V.
Evans, Eric G B
Millhauser, Glenn L.
Timofeeva, Tatiana V.
Marder, Seth R.
KAUST DepartmentPhysical Sciences and Engineering (PSE) Division
MetadataShow full item record
AbstractDimers of 2-substituted N,N'-dimethylbenzimidazoline radicals, (2-Y-DMBI)2 (Y=cyclohexyl (Cyc), ferrocenyl (Fc), ruthenocenyl (Rc)), have recently been reported as n-dopants for organic semiconductors. Here their structural and energetic characteristics are reported, along with the mechanisms by which they react with acceptors, A (PCBM, TIPS-pentacene), in solution. X-ray data and DFT calculations both indicate a longer C-C bond for (2-Cyc-DMBI)2 than (2-Fc-DMBI)2, yet DFT and ESR data show that the latter dissociates more readily due to stabilization of the radical by Fc. Depending on the energetics of dimer (D2) dissociation and of D2-to-A electron transfer, D2 reacts with A to form D+ and A- by either of two mechanisms, differing in whether the first step is endergonic dissociation or endergonic electron transfer. However, the D+/0.5D2 redox potentials-the effective reducing strengths of the dimers-vary little within the series (ca. -1.9V vs. FeCp2+/0) (Cp=cyclopentadienyl) due to cancelation of trends in the D+/0 potential and D2 dissociation energy. The implications of these findings for use of these dimers as n-dopants, and for future dopant design, are discussed. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
JournalChemistry - A European Journal
Is Supplemented ByZhang, S., Naab, B. D., Jucov, E. V., Parkin, S., Evans, E. G. B., Millhauser, G. L., … Marder, S. R. (2015). CCDC 1048481: Experimental Crystal Structure Determination [Data set]. Cambridge Crystallographic Data Centre. https://doi.org/10.5517/cc1460zb
Zhang, S., Naab, B. D., Jucov, E. V., Parkin, S., Evans, E. G. B., Millhauser, G. L., … Marder, S. R. (2015). CCDC 1048482: Experimental Crystal Structure Determination [Data set]. Cambridge Crystallographic Data Centre. https://doi.org/10.5517/cc14610d
- Dimers of nineteen-electron sandwich compounds: crystal and electronic structures, and comparison of reducing strengths.
- Authors: Mohapatra SK, Fonari A, Risko C, Yesudas K, Moudgil K, Delcamp JH, Timofeeva TV, Brédas JL, Marder SR, Barlow S
- Issue date: 2014 Nov 17
- On the mechanism of nitrosoarene-alkyne cycloaddition.
- Authors: Penoni A, Palmisano G, Zhao YL, Houk KN, Volkman J, Nicholas KM
- Issue date: 2009 Jan 21
- Light-induced oxidation of unsaturated lipids as sensitized by flavins.
- Authors: Huvaere K, Cardoso DR, Homem-de-Mello P, Westermann S, Skibsted LH
- Issue date: 2010 Apr 29
- Stabilization of oxidovanadium(IV) by organic radicals.
- Authors: Kundu S, Maity S, Maity AN, Ke SC, Ghosh P
- Issue date: 2013 Apr 7
- A DFT-Elucidated Comparison of the Solution-Phase and SAM Electrochemical Properties of Short-Chain Mercaptoalkylferrocenes: Synthetic and Spectroscopic Aspects, and the Structure of Fc-CH2CH2-S-S-CH2CH2-Fc.
- Authors: Lewtak JP, Landman M, Fernández I, Swarts JC
- Issue date: 2016 Mar 7