Structural and magnetic properties of Cu[C(CN)3]2 and Mn[C(CN)3]2

Single-crystal X-ray structure analyses and the measurements of static magnetic susceptibility and ESR have been performed for the title compounds. Crystal data: for Cu[C(CN)(3)](2), space group Pmna, a = 7.212(5) Angstrom, b = 5.452(7) Angstrom, c = 10.696(7) Angstrom, and Z = 2; for Mn[C(CN)(3)](2), space group Pmna, a = 7.742(5) Angstrom, b = 5.411(6) Angstrom, c = 10.561(6) Angstrom, and Z = 2. Both salts are essentially isostructural. The Cu atoms are bridged by two [C(CN)(3)](-) anions to form an infinite double chain structure, in which Cu has a square planar coordination (d(Cu-N) = 1.986(6) Angstrom). The third CN end of the anion is weakly coordinated to the adjacent Cu chain (d(Cu-N) = 2.47(1) Angstrom), making a three-dimensional network. The crystal is composed of two such interwoven networks. In the Mn complex, the third Mn-N distance (2.256(6) Angstrom) is as short as the equatorial coordinations (2.236(4) Angstrom), so that Mn is coordinated octahedrally. These compounds exhibit paramagnetic behavior following the Curie-Weiss law with Weiss temperatures -1.4 and -9 K, respectively, and the Mn complex undergoes an antiferromagnetic transition at T-N = 5 K.