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A theoretical explanation of the organic ferromagnetism in the β-phase of para-nitrophenyl nitronyl nitroxide

✍ Scribed by M. Okumura; K. Yamaguchi; M. Nakano; W. Mori

Publisher
Elsevier Science
Year
1993
Tongue
English
Weight
675 KB
Volume
207
Category
Article
ISSN
0009-2614

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✦ Synopsis

Molecular orbital calculations have been carried out for clusters of para-nitrophenyl nitronyl nitroxide (pNPNN) extracted from the experimental crystal structure of its p-phase. Three-dimensional effective exchange integrals (&,) are found to be positive (ferromagnetic). The ferromagnetic transition temperature is estimated by a generalized Langevin-Weiss model combined with the calculated Jab, being consistent with the observed value. A theoretical explanation is presented for the long-range ferromagnetic ordering in the pNPNN crystal. Implications of the calculated results are also discussed in relation to a theoretical possibility of organic ferromagnetism of other substituted phenyl nitronyl nitroxides.

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