Theoretical description of phenomena observed in a systematic study of the spin crossover in Fe(ii) complexes with halogenated ethyltetrazoles Part I. The model of ordering (non-specific molecular interactions)

Abstract

The theoretical model taking into account interactions of a spin-crossover molecule with its two nearest neighbours has been applied to the data on spin crossover equilibria in a series of Fe(II) complexes with halogenated ethyltetrazoles. Transition curves of different shapes, varying from a gradual to a two-step and incomplete spin crossover, have been successfully described by this model. The observed variation of the shape of transition curve originates from ligand-ligand interactions of neighbouring complexes achieved via electrostatic dipole-dipole interactions and hydrogen bonding.