Rational Design of Iron Spin-Crossover Complexes Using Heteroscorpionate Chelates.

The optical, structural, and magnetic properties of iron(II,III) sandwich complexes, Fe(Tp') (Tp' = bis(3,5-dimethylpyrazolyl)benzotriazolylborate), are described. The intensely colored Fe(Tp') (orange) and Fe(Tp') (purple) show strong MLCT bands. Geometric isomerism for M(Tp') is established crystallographically in the racemate of chiral -Fe(Tp').