Kazuhide Ogawa

Crystal structure of copper(II)mellitate, [Cu3.5C6(COO)5(COOH)(OH)2(H2O)8.5]·4.5H2O

The crystal structure of copper(II)mellitate, Cu3.5C12H29O27, has been determined by X-ray analysis. The complex crystallizes in the orthorhombic space groupIba2, with unit-cell dimensionsa=19.274(3),b=21.054(7),c=12.956(4) Å. The structure was deduced by the direct method with the help of the Patterson method and refined by the block-diagonal least-squares technique to a finalR value of 0.037 for 2995 observed reflections. Among six carboxyl groups of mellitic acid, five groups lose protons and form coordinate bonds to four copper atoms, and the remaining group forms hydrogen bonds to the water of crystallization and coordinated water. The configuration around copper is distorted-pyramidal, with the Cu-O bond distances of 1.896(7) to 2.425(7) Å.

Molecular and crystal structure of hexaaquamanganese(II) bis{bis(N-salicylideneglycinato)manganate(III)} dihydrate, [MnII(H2O)6][MnIII(Sal = Gly)2]2·2H2O

Abstract The crystal structure of hexaaquamanganese(II) bis{bis(N-salicylideneglycinato)manganate(III)} dihydrate has been determined by X-ray analysis. The complex crystallizes in the monoclinic space group I2|a, with unit-cell dimensions a = 37.431(5), b = 12.100(1), c = 9.448(1) A, β = 92.31(1)°. The structure was deduced by the direct method and refined by the block-diagonal least-squares technique to a final R value of 0.062 for 3904 observed reflections. The Mn(II) is octahedrally ligated by six water molecules, while Mn(III) is octahedrally chelated by two salicylideneglycinate ligands, of which one is nearly planar and the other considerably bent. It was discovered that the crystal is, as a whole, of a ‘sandwich’ structure made of one central sheet containing hexaaquamanganese(II)s and the water molecules of crystallization, and two outside sheets containing bis(N-salicylideneglycinato)manganate(III)s.

Molecular and crystal structure of cis-[CoIII(3-hydroxyimino-2,4-pentanedionato)2(pyridine)2] ClO4

The crystal structure of cis [Co III (3-hydroxyimino-2,4-pentanedionato) 2 (pyridine) 2 ]ClO 4 has been determined by X-ray analysis. The brown hexagonal tabular crystal are orthorhombic and the space group Pna2 1 . The unit cell dimensions are a = 17.11(1), b = 10.62(2), c = 13.65(1) A ; Z = 4. The structure was deduced by the heavy atom method and refined by the block-diagonal least-squares method to a final R value of 0.090 for 1812 observed reflections. The structure consists of the complex cation with a cis geometry and the perchlorate anion. The cobalt atom has an octahedral coordination with the two CoN(pyridine) bond distances of 1.99 and 1.99 A , and the two CoN (hydroxyiminato) bond distances of 1.88 and 1.90 A , and the two CoO bond distances of 1.88 and 1.88 A . Each of the planes of pyridine rings in the complex cation is almost perpendicular to each of the corresponding equatorial planes. The axial pyridine plane does not exactly bisect OCoN angle on the equatorial plane: it rotates about the axis of CoN (pyridine) in the range of 6° to 24° from the bisector of OCoN angle toward the CoO bond.