Towards synergy between spin-crossover and metal-ligands bond break in molecular crystals: structural investigations of eight seven-cordinated Fe(II) macrocyclic complexes

Sixteen structures of eight analogical Fe(II) macrocyclic complexes have been investigated exhibiting distinguishable structural properties even though no spin-crossover is observed. Notwithstanding, due to a synergistic effect between ligand field strength and intermolecular interaction, two of these complexes present very rare evidence for metal–ligand bond break at low temperature