Relationship between Electron Spin Resonance Hyperfine Splittings and π‐Electron Spin Densities. A First‐Order Excess Charge Effect

1965 ◽  
Vol 43 (1) ◽  
pp. 309-310 ◽  
Author(s):  
James R. Bolton
1960 ◽  
Vol 38 (4) ◽  
pp. 503-507 ◽  
Author(s):  
C. A. McDowell ◽  
J. R. Rowlands

The electron spin resonance spectra of the positive and negative ions of diphenylene have been measured. It has been found that these spectra consist of five lines showing that the observed hyperfine interaction is caused by four equivalent protons. The over-all extent of the positive ion spectrum is 18 gauss compared with that of 12.9 gauss for the negative ion. The hyperfine splittings observed are 4.0 gauss and 2.75 gauss respectively.


1975 ◽  
Vol 53 (16) ◽  
pp. 2361-2364 ◽  
Author(s):  
John Charles Tait ◽  
James Anthony Howard

A kinetic electron spin resonance study of the self-reaction of SF5 and a spectroscopic and kinetic e.s.r. study of the reaction of SF5 with 1,1-di-t-butylethylene are reported. This radical undergoes self-reaction by a second-order process and the rate constants are given by the Arrhenius equation log 2k1(M−1 s−1) = (10.3 ± 0.5) − (1.7 ± 0.5)/θ where θ = 2.303RT kcal mol−1. It adds to 1,1-di-t-butylethylene to give (t-Bu)2CCH2SF5 which decomposes by a first-order process with rate constants that obey the expression log k2(s−1) = (13 ± 0.4) − (10 ± 0.2)/θ. Both these rate constants are pertinent to kinetic studies of the photoinduced addition of SF5C1 to olefins.


Author(s):  
W. John Albery ◽  
Richard G. Compton ◽  
Andrew T. Chadwick ◽  
Barry A. Coles ◽  
Jan A. Lenkait

1972 ◽  
Vol 50 (12) ◽  
pp. 1825-1830 ◽  
Author(s):  
G. Bigam ◽  
John Hooz ◽  
Siegfried Linke ◽  
R. E. D. McClung ◽  
Melvyn W. Mosher ◽  
...  

Several ferrocenylalkyl- and aryl ketyls were generated and their e.s.r. spectra were recorded. Pentadeuterio-benzoylferrocene and benzoyl perdeuterioferrocene were synthesized. Analysis of the e.s.r. spectra of their corresponding ketyls enabled the determination of the hyperfine splitting constants of benzoylferrocene ketyl, and allowed an assignment of the electron densities at various positions in the molecule.A comparison of the magnitudes of the g-values for the ketyls derived from benzophenone (2.0034), benzoylferrocene (2.0062), and 2,2-dimethylpropanoylferrocene (2.0126), combined with the proton hyperfine splittings, gave some insight into the nature of the interaction of the free electron with the ferrocene system.


1980 ◽  
Vol 58 (15) ◽  
pp. 1592-1595 ◽  
Author(s):  
Walter Kremers ◽  
Ajit Singh

Organic spin traps have been used to study the formation of azide radicals during the reaction of azide anions with hydroxyl radicals. The azide radicals have been successfully trapped with three spin traps: 5,5-dimethylpyrroline-1-oxide (DMPO), phenyl-N-tert-bulyl nitrone (PBN), and 4-pyridyl-N-tert-butyl nitrone (PyBN). The azide radicals produced from 15N sodium azide have also been trapped. The hyperfine splittings of the resulting radicals have been determined.


Sign in / Sign up

Export Citation Format

Share Document