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Stabilization of long-lived metastable state in long alkylated spin-crossover cobalt(II) compound
Shinya Hayami1, Daisuke Urakami, Yoshihiro Kojima
1Department of Chemistry, Graduate School of Science and Technology, Kumamoto University, 2-39-1 Kurokami, Kumamoto, 860-8555 Japan. hayami@sci.kumamoto-u.ac.jp
Abstract:
The A mixed crystal compound [Co(0.8)Fe(0.2)(C16-terpy)(2)](BF(4))(2) (2) (C16-terpy is 4'-hexadecyloxy-2,2':6',2''-terpyridine) with long alkyl chains was prepared by mixing [Co(C16-terpy)(2)](BF(4))(2) (1), which exhibits unique magnetic behavior, and the diamagnetic iron(II) compound [Fe(C16-terpy)(2)](BF(4))(2) (3). The long-lived metastable state in the frozen-in effect was observed for the first time in the spin-crossover cobalt(II) compound 2. Furthermore, relaxation from metastable to stable states was very slow because of a large structural transition resulting from the long alkyl chains.
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