Die Kristallstruktur von Zinkhexajodatoplumbat(IV)-hexahydrat

Abstract

Zn[Pb(IO3)6].6H20 crystallizes in the space group P] with a= 6"905 (7), b= 7"285 (6), c= 10.976 (9) /~, ~=97.2 (1) °, p= 104.15 (8) °, y=88.11 (8) °, Z=I. The intensities were collected on a four-circle diffractometer and corrected for absorption. The crystal structure was determined by the heavy-atom method. Refinement by the least-squares method with anisotropic temperature factors for the heavy atoms (Pb, I,Zn) and isotropic temperature factors for the O atoms converged at R= 4.9 %. The Pb atoms are surrounded by six O atoms belonging to the six -O-102 groups. The O atoms form a distorted octahedron; in particular the distance Pb-O(4) is very short (2-070 A). The I atoms are also surrounded by six O atoms but the octahedron is very distorted. For each I atom there are three I-O distances between 1.766 and 1"898 ,& and three more between 2.546 and 3"083 ~. An interesting feature of the structure is the coordination of the Zn atoms. There is no [Zn(H20)6] 2+ octahedron but instead an octahedron formed by four water molecules and two O atoms of the iodate groups. The other water molecules are embedded in the structure as real structure water. All parts of the structure are linked together by hydrogen bonds.

ZnIO3(OH): a new layered noncentrosymmetric polar iodate – hydrothermal synthesis, crystal structure, and second-harmonic generating (SHG) properties

“…We have focused our attention on the Zn 2+ − I 5+ −oxide system, since the cooperation effect of both the d 10 and the lone pair cations with asymmetric structural geometry may increase the probability of producing NCS materials. In fact, several materials in the Zn 2+ −I 5+ −oxide system have been reported and they are structurally quite different; K 2 Zn(IO 3 ) 4 (H 2 O) 2 8 exhibits a NCS zero-dimensional molecular structure, ZnPb(IO 3 ) 6 •6H 2 O 9 and Zn(IO 3 ) 2 •2H 2 O 10 have CS one-dimensional chain structures, and Zn(IO 3 ) 2 11,12 shows a NCS three-dimensional structure. Here we report hydrothermal synthesis, structural determination, and characterization of a new NCS polar zinc iodate material, ZnIO 3 (OH).…”

Structure and magnetism in a hydroxy bridged binuclear copper(II) system with a "tunable" binuclear centre

“…The structure of the iodate complex is also of special interest because of the role of the iodate groups. Examples of inorganic compounds involving ionic, monodentate, bidentate, and even tridentate iodate have been reported (26)(27)(28)(29) where the polyfunctional nature of the iodate often involves loosely bound layers and chains of metal centres. However, examples of coordination complexes involving nitrogen donor ligands and bound iodate appear to be lacking and the structure of [ C U~( P A P ) ( O H ) ( I O~)~] .~H~ may be the first exainple of such a system involving iodates with mixed functionality.…”