Influence of Pressure on the Intramolecular Spin Exchange in a Short Imidazolium-Nitroxide Biradical
- Authors: Mladenova-Kattnig B.1, Grampp G.1, Kokorin A.I.2
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Affiliations:
- Institute of Physical and Theoretical Chemistry, Graz University of Technology
- N. N. Semenov Institute of Chemical Physics, Russian Academy of Sciences
- Issue: Vol 48, No 4 (2017)
- Pages: 327-334
- Section: Original Paper
- URL: https://journals.rcsi.science/0937-9347/article/view/247664
- DOI: https://doi.org/10.1007/s00723-017-0865-1
- ID: 247664
Cite item
Abstract
A short-chain imidazoline-type nitroxide biradical R5NO–CH=N–N=C(CH3)–R5N, B2, with nitroxide rings R5N and R5NO as 1-oxyl-2,2,5,5-tetramethyl-3-imidazoline and 1-oxyl-2,2,5,5-tetramethyl-3-N-oxide imidazoline, respectively, has been studied using X-band electron paramagnetic resonance (EPR) spectroscopy in CH3CN solutions at variable temperature T and pressure P. Changes of the solution viscosity on the intramolecular electron spin exchange in B2 is characterized by calculating the value of the exchange integral |J/a|, where a denotes the 14N hyperfine splitting (hfs) constant. It is revealed that the intramolecular dynamics in B2 do not follow the Debye–Stokes–Einstein law, while the Arrhenius dependence is fulfilled. Probable reasons of such behavior are discussed.
About the authors
Boryana Mladenova-Kattnig
Institute of Physical and Theoretical Chemistry, Graz University of Technology
Email: alex-kokorin@yandex.ru
Austria, Graz
Günter Grampp
Institute of Physical and Theoretical Chemistry, Graz University of Technology
Email: alex-kokorin@yandex.ru
Austria, Graz
Alexander I. Kokorin
N. N. Semenov Institute of Chemical Physics, Russian Academy of Sciences
Author for correspondence.
Email: alex-kokorin@yandex.ru
Russian Federation, Moscow