Ligand effects in a heteroleptic bis-tridentate iron( iii ) spin crossover complex showing a very high T 1/2 value

We describe the first example of a bis-tridentate heteroleptic iron(iii) spin crossover (SCO) complex, [Fe(3-OMe-SalEen)(thsa)]. Compared to the parent homoleptic compounds, the spin crossover features in the heteroleptic species are enhanced with a gradual-abrupt spin transition at 344 K. Clear correlations between π-π interactions and the T1/2 value have been revealed.