Dependence of electron paramagnetic resonance spectral lineshapes on molecular tumbling: Nitroxide radical in water:glycerol mixtures. (29th April 2018)

• Record Type: Journal Article
• Authors: Clark, Ashley; Sedhom, Jessica; Elajaili, Hanan; Eaton, Gareth R.; Eaton, Sandra S.
• Is Part Of: Concepts in magnetic resonance. Volume 45A:Number 5(2016)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2018-04-29
• Subjects: electron paramagnetic resonance -- nitroxide radicals -- Stokes‐Einstein -- tumbling; Magnetic resonance -- Periodicals; Nuclear magnetic resonance -- Periodicals; 538
• DOI: 10.1002/cmr.a.21423
• Languages: English
• ISSNs: 1546-6086

Abstract

Abstract: Electron paramagnetic resonance spectra of nitroxide radicals are reporters of molecular tumbling correlation times. The concepts of electron paramagnetic resonance and molecular tumbling are demonstrated by examination of spectra of the radical tempol (4‐hydroxy‐2, 2, 6, 6‐tetramethylpiperidin‐1‐oxyl) in water:glycerol mixtures. Analysis of the spectral line shapes with the Kivelson model and computer simulation with EasySpin are discussed. Values of the tumbling correlation times obtained by the two methods are shown to be in good agreement. Comparison of the experimental tumbling correlation times with values calculated with the Stokes‐Einstein model indicates a slip coefficient of 0.066, which is consistent with other reports for nitroxides in various solvents.