trans-Bis(cyano-kappaC)(1,4,8,11-tetraazacyclotetradecane-kappa4N)manganese(III) perchlorate, a low-spin manganese(III) complex.

The crystal structure of the low-spin (S = 1) MnIII complex [Mn(CN)(2)(C(10)H(24)N(4))]ClO(4), or trans-[Mn(CN)(2)(cyclam)](ClO(4)) (cyclam is the tetradentate amine ligand 1,4,8,11-tetraazacyclotetradecane), is reported. The structural parameters in the Mn(cyclam) moiety are found to be insensitive to both the spin and the oxidation state of the Mn ion. The difference between high- and low-spin Mn(III) complexes is that a pronounced tetragonal elongation of the coordination octahedron occurs in high-spin complexes and a slight tetragonal compression is seen in low-spin complexes, as in the title complex.