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Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Spin transition at the mesophase transition temperature in a cobalt(II) compound with branched alkyl chains
Shinya Hayami1, Reiko Moriyama, Aya Shuto
1Department of Chemistry, Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-hiroshima 739-8526, Japan. hayami@ hiroshima-u.ac.jp
Abstract:
A cobalt(II) compound, [Co(C5C12C10-terpy)2](BF4)2 [C5C12C10-terpy = 4',5' ''-decyl-1' ''-(heptadecyloxy)-2,2':6',2' '-terpyridine] with branched alkyl chains, based on a terpyridine frame, was synthesized. The cobalt(II) compound exhibits a spin transition between low-spin and high-spin with a thermal hysteresis loop (T(1/2) upward arrow = 288 K and T(1/2) downward arrow = 284 K) at the liquid-crystal transition temperature. It is the first example in the cobalt(II) compounds in which the spin transition occurs at the crystal-liquid crystal transition temperature.
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