Fe(II) spin-crossover phenomenon in the pentadecanuclear {Fe9[Re(CN)8]6} spherical cluster.

The self-assembly of iron(II) ions with rare octacyanidorhenate(V) metalloligands in a methanolic solution results in the formation of a nanometric pentadecanuclear {Fe(II) 9 [Re(V) (CN)8 ]6 (MeOH)24 }⋅10 MeOH (1) molecule with a six-capped body-centered cubic topology. The cluster demonstrates a thermally-induced spin-crossover phase transition at T1/2 =195 K which occurs selectively for a single Fe(II)  ion embedded in the center of a cluster core.