The crystal structure of synthetic lautarite, Ca(IO₃)₂

Abstract

Synthetic lautarite, Ca(IO3)2, is monoclinic, space group P2~/n, with cell dimensions a = 7.143 (1), b = 11.297 (3), c = 7.2804 (9) A, fl = 106.35 (1) °, Z = 4. The structure has been determined by the heavy-atom method and refined by the full-matrix least-squares method to an R factor of 0.055 for 2044 reflections, measured on an automatic single-crystal diffractometer. The Ca atom is eight-coordinated (av. Ca-O distance 2.492 A), the CaO 8 polyhedron being a distorted hexagonal bipyramid. The average I-O bond lengths (and O-I-O bond angles) within the I(1)O 3 and I(2)O~ groups are 1.807/k (101.7 °) and 1.804/k (97.0 °) respectively. I(1) is weakly bonded to three further O atoms at an average distance of 2.964 A, the I(1)O 6 polyhedron being a distorted octahedron. I(2) is further bonded to four O atoms at an average distance of 2.994 A; the I(2)O 7 polyhedron is a trigonal antiprism, modified by an additional corner above a prism face. The structure of Ca(IO3) 2 is a tightly bonded three-dimensional framework, formed by Ca polyhedral chains crosslinked by the iodate groups.

From Layered Basic Zinc Acetate Nanobelts to Hierarchical Zinc Oxide Nanostructures and Porous Zinc Oxide Nanobelts

“…This beltlike BLBZA nanostructure has potential for functional materials, such as separation or anionic exchange materials, and for electrical devices. [41][42][43][44][45][46][47][48][49] The obtained BLBZA nanobelts were further characterized by transmission electron microscopy (TEM). Figure 3a-c shows typical TEM images of the product, confirming that the as-synthesized sample is dominated by beltlike nanostructures.…”

“…[41][42][43][44][45][46][47][48][49] These materials are known for the special features based on their layered crystal structure. When there is only one kind of metal cation, the HDS compound is called a layered hydroxide metal salt or layered basic metal salt.…”

“…When there is only one kind of metal cation, the HDS compound is called a layered hydroxide metal salt or layered basic metal salt. An important example is layered basic zinc salt (LBZS), for example, Zn 5 (OH) 8 Cl 2 ·n H 2 O, [41] Zn 5 (OH) 8 (NO 3 ) 2 ·2 H 2 O, [43,47,48] or Zn 5 (OH) 8 (CH 3 COO) 2 ·2 H 2 O. [47][48][49] LBZS consists of a stacking of brucite-type polynuclear zinc hydroxyl layers.…”

The crystal structure and magnetic behaviour of γ-Cu(IO3)2

“…H20 (Manotti-Lanfredi, PellingheUi, Tiripicchio & Camellini, 1972), Nd(103) 2. H20 (Liminga, Abrahams & Bernstein, 1975a) and Ca(IO3) 2, lautarite (Ghose, Wan & Wittke, 1978). On the other hand a-Cu(IO3) 2 crystallizes in a polar space group, where the iodate ions form a nearly regular hexagonal close-packed array (Liminga, Abrahams & Bernstein, 1975b).…”

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.…”