Ligand Deprotonation and Spin Crossover in Fe(II) Complex

The effect of deprotonation of the hydrazine-based ditopic isomeric terpyridine-like ligand on the spin crossover behavior of the Fe(II) complex is studied. The deprotonation is modelled by the appearance of a negative charge on the nitrogen ions from the first coordination sphere of the iron ion. It is demonstrated that depending on the distribution of this negative charge on the nitrogen ions, deprotonation can either prevent or facilitate spin conversion.