Series of TEMPO-substituted norbornadiene, spiropyran and anthracene derivatives have been prepared; their light-induced structural change to the corresponding qudricyclanes. merocyanines or anthracene-dimers and the reverse reactions to the starting materials have been studied. The antiferromagnetic or ferromagnetic behavior observed in norbornadienes/anthracenes was found to be preserved in the corresponding quadricyclanes/anthracene-dimers in spite of the difference of their Weiss temperatures, whereas switching of the intermolecular magnetic interactions was observed in spiropyran/merocyanine systems.
Takeuchi, Soichi; Ogawa, Yuya; Naito, Akira, Molecular Crystals and Liquid Crystals Science and Technology, Section A: Molecular Crystals and Liquid Crystals, 2000, vol. 345, p. 491/167 - 496/172