Antiferromagnetic exchange interaction among the three spins placed in an isosceles triangular configuration in 2,4-dimethoxy-1,3,5-benzenetriyltris(N-tert-butyl nitroxide)

Journal of the American Chemical Society

Volumn 118, Issue 39, 1996, Pages 9347-9351

  Fujita, Junpei ^a   Tanaka, Masakazu ^a   Suemune, Hiroshi ^a   Koga, Noboru ^a   Matsuda, Kenji ^a   Iwamura, Hiizu ^a  

^a KYUSHU UNIVERSITY   (Japan)

Author keywords

[No Author keywords available]

Indexed keywords

FERROMAGNETIC MATERIAL; NITROXIDE;

ARTICLE; DRUG STRUCTURE; DRUG SYNTHESIS; ELECTRON SPIN RESONANCE; X RAY ANALYSIS;

EID: 0029857173     PISSN: 00027863     EISSN: None     Source Type: Journal    
DOI: 10.1021/ja961849b     Document Type: Article

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25. B = -7 K for biradical 2.
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27. Kahn, O. Molecular Magnetism; VCH: New York, 1993; Chapter 10.
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30. A), between them are 65.1, 75.3°, and 5.13 Å, respectively.
31. The simulation of the EPR fine structure was performed by using a program based on the second-order perturbation theory and provided by Professors K. Ito and K. Takui of Osaka City University.
32. In an EPR spectrum of a sample of 3 doped in poly(vinyl chloride) (PVC) film (3:PVC = 1:200 w/w) prepared under conditions similar to those for the recrystallization, a shoulder was more clearly observed for the central signal and the signal intensity due to the quartet species vs 1/T plot did not obey Curie's law.
33. The observed discrepancy of thermal behavior of 3 obtained from EPR spectrometry and SQUID susceptometry may be explained by the difference of conformation in the crystalline state and solid solutions; in the latter, the dihedral angle between the planes of nitroxide radicals and benzene ring might be smaller.
34. In eq 2, all the symbols have their usual meanings and g = 2.0066 as determined by the EPR spectrum of a powder sample of 3.
35. Bleaney, B.; Bowers, K. D. Proc. R. Soc. London 1952, A214, 451. For fitting to the experimental data, g = 2.0058 as obtained by the EPR spectrum of a powder sample of 4.