Coquandite, Sb6+xO8+x(SO4)(OH)x•(H2O)1-x (x=0.3), from the Cetine mine, Tuscany, Italy: crystal structure and revision of the chemical formula

被引:0
|
作者
Bindi, L. [1 ,2 ]
Biagioni, C. [3 ]
Ceccantini, L. [4 ]
Batoni, M. [4 ]
Menchetti, S. [1 ]
机构
[1] Univ Firenze, Dipartimento Sci Terra, I-50121 Florence, Italy
[2] CNR Ist Geosci & Georisorse, Sez Firenze, I-50121 Florence, Italy
[3] Univ Pisa, Dipartimento Sci Terra, I-56126 Pisa, Italy
[4] Grp Mineral Fiorentino, I-56126 Florence, Italy
关键词
coquandite; Sb-sulfates; structure solution; crystal-structure refinement; Cetine mine; BOND-VALENCE; CASB4O4(OH)2(SO4)2.2H2O; PERETAITE;
D O I
10.1180/minmag.2014.078.4.08
中图分类号
P57 [矿物学];
学科分类号
070901 ;
摘要
The crystal structure of the mineral coquandite, a rare Sb oxy-sulfate hydrate, was solved using intensity data collected from a crystal from the Cetine mine, Tuscany, Italy. This study revealed that the structure is triclinic, space group P (1) over bar, with a = 11.4292(5), b = 29.772(1), c = 11.2989(5) angstrom, alpha = 91.152(3), beta = 119.266(4), gamma = 92.624(3)degrees and V = 3346.4(2) angstrom(3). The refinement of an anisotropic model led to an R index of 0.0347 for 21,061 independent reflections. Thirty-two Sb sites, five S sites and 67 oxygen sites occur in the crystal structure of coquandite. Sb atoms display the characteristic SbO3E and SbO4E coordinations whereas S fills (SO4) tetrahedral groups. These atoms are arranged in five symmetry-independent layers perpendicular to b*. Four of them and their centrosymmetrical counterparts form complex modules stacked along b* and bonded through two Sb atoms and H bonds. The complex H bonding system in the structure is discussed. On the basis of information gained from this characterization, the crystal-chemical formula was revised according to the structural results, yielding Sb6+xO8+x(SO4)(OH)(x)center dot(H2O)(1-x) (Z = 10) with x = 0.3 instead of Sb6O8(SO4)center dot H2O (Z = 12) as reported previously. A recalculation of the chemical data listed in the scientific literature for coquandite according to the structural results obtained here leads to a satisfactory agreement.
引用
收藏
页码:871 / 888
页数:18
相关论文
共 50 条
  • [31] Refinement of the crystal structure of [Rbx(NH4)1-x]3H(SO4)2 (x=0.11) by sincyle-crystal X-ray and neutron diffraction:: I.: phase II at 300 K
    Smirnov, L. S.
    Wozniak, K.
    Dominiak, P.
    Loose, A.
    Natkaniec, I.
    Frontasyeva, M. V.
    Pomyakushina, E. V.
    Baranov, A. I.
    Dolbinina, V. V.
    CRYSTALLOGRAPHY REPORTS, 2008, 53 (03) : 418 - 427
  • [32] Crystal-chemistry of sulfates from Apuan Alps (Tuscany, Italy). I. Crystal structure and hydrogen bond system of melanterite, Fe(H2O)6(SO4)•H2O
    Mauro, Daniela
    Biagioni, Cristian
    Pasero, Marco
    PERIODICO DI MINERALOGIA, 2018, 87 (01): : 89 - 96
  • [33] Positronium formation and inhibition in binary ionic solid solutions of general formula Al(1-x)Cr(x)K(SO4)2•12 H2O:: A positron annihilation lifetime and Doppler broadening spectroscopy study
    Machado, JC
    de Lima, GM
    Oliveira, FC
    Marzano, IM
    CHEMICAL PHYSICS LETTERS, 2006, 418 (1-3) : 292 - 295
  • [34] The Influence of Supercooling and Hydrodynamics on the Mosaic and Radial Inhomogeneity of K2NiXCo(1-X)(SO4)2•6H2O Mixed Crystal
    Vasilyeva, Natalia A.
    Rudneva, Elena B.
    Manomenova, Vera L.
    Grigoriev, Yuriy V.
    Voloshin, Alexey E.
    CRYSTALS, 2021, 11 (11)
  • [35] Characterization of perovskite systems derived from Ba2In2O5▭ -: Part II:: The proton compounds Ba2In2(1-x)Ti2xO4+2x(OH)y[0≤x≤1; y≤2(1-x)]
    Jayaraman, V
    Magrez, A
    Caldes, M
    Joubert, O
    Taulelle, F
    Rodriguez-Carvajal, J
    Piffard, Y
    Brohan, L
    SOLID STATE IONICS, 2004, 170 (1-2) : 25 - 32
  • [36] Growth of faces of K2Co x Ni1-x (SO4)2 • 6H2O mixed crystals
    Vorontsov, D. A.
    Voloshin, A. E.
    Grebenev, V. V.
    Vasilieva, N. A.
    Kim, E. L.
    Manomenova, V. L.
    Rudneva, E. B.
    Masalov, V. M.
    Zhokhov, A. A.
    Emelchenko, G. A.
    CRYSTALLOGRAPHY REPORTS, 2017, 62 (06) : 976 - 982
  • [37] Growth and properties of mixed K2Ni x Co1-x (SO4)2 • 6H2O crystals
    Vasilyeva, N. A.
    Grigoryeva, M. S.
    Grebenev, V. V.
    Voloshin, A. E.
    CRYSTALLOGRAPHY REPORTS, 2013, 58 (04) : 646 - 650
  • [38] Elemental analysis of mixed K2Ni x Co1-x (SO4)2 a™ 6H2O crystals
    Vasilyev, N. A.
    Nuzhdin, D. S.
    Faddeev, M. A.
    Grebenev, V. V.
    Lykov, V. A.
    Voloshin, A. E.
    CRYSTALLOGRAPHY REPORTS, 2016, 61 (02) : 304 - 307
  • [39] Growth and structure of K2NixCo(1–x)(SO4)2 · 6H2O single crystals
    N. A. Vasilyeva
    N. I. Sorokina
    A. M. Antipin
    I. A. Verin
    A. E. Voloshin
    Crystallography Reports, 2016, 61 : 11 - 17
  • [40] STUDIES ON ALKALINE-EARTH SULFITES .6. THERMAL DEHYDRATION OF CA(SO3)X(SO4)1-X.4H2O
    ZANGEN, M
    COHEN, A
    THERMOCHIMICA ACTA, 1985, 85 (APR) : 107 - 110