A quarter of a century after its synthesis and with >200 papers based on its use, `Co(CO3)0.5(OH)·0.11H2O′ proves to be Co6(CO3)2(OH)8·H2O from synchrotron powder diffraction data. Issue 1 (18th December 2018)

• Record Type: Journal Article
• Authors: Bhojane, Prateek; Le Bail, Armel; Shirage, Parasharam M.
• Is Part Of: Acta crystallographica. Volume 75:Issue 1(2019)
• Page Start: 61
• Page End: 64
• Publication Date: 2018-12-18
• Subjects: cobalt(II) carbonate hydroxide hydrate -- powder diffraction -- ab initio -- synchrotron -- malachite; Crystallography -- Periodicals; Crystals -- Periodicals; 548.3
• DOI: 10.1107/S2053229618017734
• Languages: English
• ISSNs: 2053-2296

Abstract

Abstract : The crystal structure of Co6 (CO3 )2 (OH)8 ·H2 O was solved ab initio and refined from synchrotron powder diffraction data. Abstract : The successful attempt to solve the crystal structure of Co(CO3 )0.5 (OH)·0.11H2 O (denotedCCH ), based on synchrotron powder diffraction data, leads to a drastic revision of the chemical formula to Co6 (CO3 )2 (OH)8 ·H2 O [hexacobalt(II) bis(carbonate) octahydroxide monohydrate] and to a hexagonal cell instead of the orthorhombic cell suggested previously [Porta et al. (1992). J. Chem. Soc. Faraday Trans. 88, 311–319]. This results in a new structure‐type related to malachite involving infinite chains of [CoO6 ] octahedra sharing edges along a short c axis, delimiting tunnels having a three‐branched star section. All reports discussing cobalt hydroxycarbonates (CCH ) without any structural knowledge and especially its topotactic decomposition into Co3 O4 have, as a result, to be reconsidered.