• journal_title：American Mineralogist
• Contributor：Jakub Plášil ; Karla Fejfarová ; Kia Sheree Wallwork ; Michal Dušek ; Radek Škoda ; Jiří Sejkora ; Jiří Čejka ; František Veselovský ; Jan Hloušek ; Nicolas Meisser ; Joël Brugger
• Publisher：Mineralogical Society of America
• Date：2012-
• Format：text/html
• Language：en
• Identifier：10.2138/am.2012.4127
• journal_abbrev：American Mineralogist
• issn：0003-004X
• volume：97
• issue：10
• firstpage：1796
• section：Articles

The crystal structure of pseudojohannite from White Canyon, Utah, was solved by charge-flipping from single-crystal X-ray diffraction data and refined to an R_obs = 0.0347, based on 2664 observed reflections. Pseudojohannite from White Canyon is triclinic, P1̄, with a = 8.6744(4), b = 8.8692(4), c = 10.0090(5) Å, α = 72.105(4)°, β = 70.544(4)°, γ = 76.035(4)°, and V = 682.61(5) ų, with Z = 1 and chemical formula Cu₃(OH)₂[(UO₂)₄O₄(SO₄)₂](H₂O)₁₂. The crystal structure of pseudojohannite is built up from sheets of zippeite topology that do not contain any OH groups; these sheets are identical to those found in zippeites containing Mg²⁺, Co²⁺, and Zn²⁺. The two Cu²⁺ sites in pseudojohannite are [5]- and [6]-coordinated by H₂O molecules and OH groups. The crystal structure of the pseudojohannite holotype specimen from Jáchymov was refined using Rietveld refinement of high-resolution powder diffraction data. Results indicate that the crystal structures of pseudojohannite from White Canyon and Jáchymov are identical.