• Spin crossover;
  • Cobalt;
  • Substituent effects;
  • Liquid crystals;
  • Magnetic properties;
  • Soft materials


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.