Magnetic Behavior and Liquid-Crystal Properties in Spin-Crossover Cobalt(II) Compounds with Long Alkyl Chains

Long-chain-alkylated terpyridine cobalt(II) complexes provide an opportunity for the study not only of their unique physical properties but also of the synchronicity between spin-state transitions and crystal liquid-crystal phase transitions because the thermal motion of the long alkyl chains leads to a synergetic effect exerted by external stimuli. This microreview presents recent results of terpyridine cobalt(II) complexes bearing a variety of long alkyl chains with a particular focus on the structural features as well as magnetic and liquid-crystalline properties. In addition, various influences, such as the size of the counter anion, the polarity of the terminal substituent, and mixed metal-ion systems, on the magnetic properties of these complexes are also discussed.