Biomedical subjects

Sergei D Kirik

Publications and source records attributed to Sergei D Kirik.

4 recordsLinked to original sources

PubMed2006

cis-Amminedichloroisopropylamineplatinum(II) by X-ray powder diffraction analysis.

The title compound, [PtCl2(C3H9N)(NH3)], was obtained from potassium tetrachloroplatinate(II) by a two-step route. Ab initio crystal structure determination was carried out using X-ray powder diffraction techniques. Patterson and Fourier syntheses were used for the atom locations and the Rietveld technique for the final structure refinement. The Pt coordination is close to planar, with Cl atoms in a cis orientation. Molecules are combined into groups of two molecules, with antiparallel PtN2Cl2 planes and a shortest Pt...Pt distance of 3.42 angstroms. The molecule groups are packed in a parquet motif into corrugated layers parallel to ab. The molecules in the layers are linked by H-N...Cl hydrogen bonds.

Models, Molecular↗

PubMed2005

[Pd8(CH3COO)8(NO)8]: solution from X-ray powder diffraction data.

The water-insoluble title compound, octakis(mu-acetato-kappa2O:O)octakis(mu-nitroso-kappa2N:O)octapalladium(II), [Pd8(CH3COO)8(NO)8], was precipitated as a yellow powder from a solution of palladium nitrate in nitric acid by adding acetic acid. Ab initio crystal structure determination was carried out using X-ray powder diffraction techniques. Patterson and Fourier syntheses were used for atom locations, and the Rietveld technique was used for the final structure refinement. The crystal structure is of a molecular type. The skeleton of the [Pd8(CH3COO)8(NO)8] molecule is constructed as a tetragonal prism with Pd atoms at the vertices. The eight NO- groups are in bridging positions along the horizontal edges of the prism. The N and O atoms of each nitroso group coordinate two different Pd atoms. The vertical edges present PdPd contacts with a short distance of 2.865 (1) A. These Pd atoms are bridged by a pair of acetate groups in a cis orientation with respect to each other. The complex has crystallographically imposed 4/m symmetry; all C atoms of the acetate groups are on mirror planes. The unique Pd atom lies in a general position and has square-planar coordination, consisting of three O and one N atom.

Journal Article↗

PubMed2004

[Pd(CH3COO)2]n from X-ray powder diffraction data.

The water-insoluble title compound, catena-poly[palladium(II)-di-mu-acetato-kappa4O:O'], [Pd(C2H3O2)2]n, was obtained from a nitratopalladium solution and acetic acid as a pale-pink powder. Ab initio crystal structure determination was carried out using X-ray powder diffraction techniques. Patterson and Fourier syntheses were used for atom location and the Rietveld technique was applied for the final structure refinement. The structure consists of palladium acetate complexes connected into polymeric chains running along b, in which two Pd atoms are bridged by two acetate groups that are in a cis configuration with respect to one another. The unique Pd atom lies on a site with 2/m symmetry and the acetate moieties have imposed m symmetry; these are joined into infinite chains running along the b direction. The shortest Pd...Pd distance in the row is 2.9192 (1) A. The planes of adjacent palladium complexes are inclined towards each other, the angle between the planes being approximately 30 degrees.

Journal Article↗

PubMed2002

LiNa2AlF6: a powder structure solution.

Lithium sodium aluminium fluoride was obtained as a white powder by melting a stoichiometric mixture of AlF(3), NaF and LiF at 1223 K, and then cooling to 923 K and sintering at this temperature for 4 h. The ab initio crystal structure determination was carried out using X-ray powder diffraction techniques. The monoclinic structure of LiNa(2)AlF(6) can be related to cubic elpasolite. The Li and Al atoms lie on inversion centres. The main octahedral AlF(6) structural elements are not deformed, but are rotated slightly with respect to the unit-cell axes. The Li atoms have octahedral coordinations, whereas the Na atoms have cubo-octahedral coordinations. The Na coordination polyhedron is distorted in comparison with that of elpasolite.

Journal Article↗