Isolation and molecular structure of hexacyanoruthenate(III)

The Ru(CN)(6)](3-) ion is synthesized in aqueous solution and isolated as Ph(4)As](3)Ru(CN)(6)].2H(2)O (1). Compound 1 crystallizes as orange needles in the monoclinic space group P2(1)/n with cell parameters a = 11.346(2) A, b = 23.107(5) A, c = 25.015(5) A, beta = 99.55(3) degrees, V = 6467.1(22) A(3), Z = 4. The octahedral anion has Ru-C bond lengths in the range 2.023(6)-2.066(6) A. DFT calculations reproduce experimental geometries for M(CN)(6)](3-) (M = Fe, Ru) equally well and yield significantly higher spin densities on the cyanide ligands in M(CN)(6)](3-) (M = Ru, Os) than in Fe(CN)(6)](3-).