Magnetic and electrochemical properties of corner-like and grid-like complexes resulting from the self-assembly of two structurally related bis(hydrazones) and iron (II)

[Display omitted] •The synthesis of iron (II) complexes using two ditopic ligands with a small structural difference in the hydrazone groups.•The structural features of the ligands drive the assembly of the metal complexes.•The electrochemical behaviour of iron(II) complexes is modulated by the conformation of the bis(hydrazone) ligand. Without a templated mechanism, a new corner-like complex ([Fe(C25H32N8S)2]2+=[Fe]) and a new grid-like one ([Fe4(C23H28N8S)4]8+=[Fe4]) were obtained from the self-assembly of two structurally related bis(hydrazones) (C25H32N8S = 1; C23H28N8S = 2) with Fe(II) under identical reaction conditions, commonly employed for the efficient synthesis of grid-like complexes. The electrochemical and magnetic properties of these complexes were studied. Both complexes undergo a Fe(II)/Fe(I) reduction process in each of their metal centers, but only the grid-like complex exhibits easily oxidizable metal centers. In the solid state, both complexes are in the low spin state within a wide range of temperatures, but the corner also exhibits several types of high spin states coexisting at all times. From an exploratory viewpoint, our results are important to carry out the eventual synthesis of metal complexes with suitable properties for nanotechnological applications.