Layered calcium hydrogen selenite chlorides Ca(HSeO 3 )Cl and Ca(HSeO 3 )Cl(H 2 O), the first halides obtained in СaCl 2 –H 2 SeO 3 –H 2 O system

International audienceAbstract Synthesis, crystal structures and IR spectra of the first representatives of calcium hydrogen selenite halides are reported. Colourless prismatic crystals of calcium hydrogen selenite chloride Ca(HSeO 3 )Cl and corresponding hydrated analogue Ca(HSeO 3 )Cl(H 2 O) were produced upon evaporation of aqueous solutions. Ca(HSeO 3 )Cl is monoclinic, P 2 1 / c , a = 7.0031(11) Å, b = 7.7336(12) Å, c = 8.5024(13) Å, β = 109.889(3)°, V = 433.02(12) Å 3 , R 1 = 0.039. Ca(HSeO 3 )Cl(H 2 O) is orthorhombic, Pbca , a = 6.222(4) Å, b = 10.413(7) Å, c = 16.875(10) Å, V = 1093.3 (12) Å 3 , R 1 = 0.041. Ca(HSeO 3 )Cl and Ca(HSeO 3 )Cl(H 2 O) represent new structure types. In both structures, Ca 2+ cations adopt mixed-ligand environments formed by oxygen atoms of hydrogen selenite anions (and water molecules for Ca(HSeO 3 )Cl(H 2 O)) and chloride ions. Both structures are layered. The crystal structure of Ca(HSeO 3 )Cl(H 2 O) demonstrates a rare phenomenon of hydrogen-bonded assembly of water and chloride in the interlayer space

Molecular inorganic polymers: synthesis and crystal structures of KCl72H 2 SeO 3 and CsCl7H 2 SeO 3

International audienceAbstract KCl72H 2 SeO 3 and CsCl7H 2 SeO 3 have been synthesized using solution evaporation methods from aqueous solution. Both compounds are monoclinic ( P 2/ n and P 2 1 / c ) and demonstrate new structure types. One symmetrically unique SeO(OH) 2 molecule is present in each structure. SeO(OH) 2 molecules via strong hydrogen bonds form chains in KCl72H 2 SeO 3 and layers in ?sCl7H 2 SeO 3 . The structures of KCl72H 2 SeO 3 and CsCl7H 2 SeO 3 can be described as consisting of ionic KCl chains and CsCl layers incorporated into the covalent- and hydrogen-bonded H 2 SeO 3 matrix. To the best of our knowledge, the cases when selenious acid acts as a contributor to the molecular building blocks of salt-inclusion structures are not known to date

Li2(Se2O5)(H2O)1.5·CuCl2: a salt-inclusion diselenite structurally based on tetranuclear Li4 complexes

International audienceA new lithium copper diselenite chloride hydrate, Li 2 Se 2 O 5 (H 2 O) 1.5 ·CuCl 2 , was prepared from aqueous solution

Protonated Organic Diamines as Templates for Layered and Microporous Structures: Synthesis, Crystal Chemistry, and Structural Trends among the Compounds Formed in Aqueous Systems Transition Metal Halide or Nitrate–Diamine–Selenious Acid

Systematic studies of crystalline compounds formed in aqueous systems containing aliphatic diamines, divalent transition metal halides, and selenious acid resulted in the discovery of a large family of new complex species corresponding to several new structure types. With ethylenediamine (en), layered (enH2)[M(HSeO3)2X2] compounds are the most commonly formed species which constitute a significant contribution to the family of layered hydrogen selenites containing neutral [M(HSeO3)2] (M = Mg, Mn, Co, Ni, Cu, Zn, Cd) 2D building blocks. In contrast to some previous suggestions, piperazine (pip), as well as its homologue N-methylpiperazine, mostly give rise to quite different, sometimes more complex, structures of varied dimensionality while the (pipH2)[M(HSeO3)2X2] compounds are formed only with M = Cu and Cd. In addition, metal-, halide-, or selenium-free by-product species are observed. The SeIV can be present in a multitude of forms, including H2SeO3, HSeO3−, SeO32−, and Se2O52−, reflecting amazing adaptability to the shape of the templating cations