Co‐crystallization as a Strategy for Tuning Spin Crossover Properties of Mononuclear Mn(III) Schiff‐base Complexes

Abstract We present co‐crystallization as an approach to tuning spin crossover (SCO) properties of mononuclear Mn(III) Schiff‐base complexes. Complexes [Mn(5‐F‐sal‐N‐1,5,8,12)]ClO 4 ⋅ 0.5carbazole (cocrystal 1 a ) and [Mn(5‐F‐sal‐N‐1,5,8,12)]PF 6 ⋅ 0.5carbazole (cocrystal 2 b ) are synthesized by the co‐crystallization of their parent complexes ( [Mn(5‐F‐sal‐N‐1,5,8,12)]Y, Y=ClO 4 − ( 1 ); Y=PF 6 − ( 2 ) ) with the carbazole and they both exhibit HS electronic configurations between 2 and 300 K. While, the parent complex 1 shows a nearly complete SCO with T 1/2 =100 K and complex 2 maintains a high‐spin (HS) state. The introduction of carbazole as the third component has a great influence on cation‐anion crystal packing and finally the cooperative effects of the SCO complexes.