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The crystal structure of the mineral gortdrumite, a rare copper-mercury-iron sulfide, was solved using intensity data collected using a crystal from the Neuschurf adit, Leogang, Salzburg, Austria. This study revealed that the structure is triclinic, space group P $\bar 1$ , with cell parameters: a = 9.677(4), b = 9.865(5), c = 11.992(5) Å, α = 77.85(4), β = 79.42(3), γ = 76.30(4)°, V = 1076.5(8) Å3 and Z = 1. The refinement led to an R index of 0.0833 for 3335 independent reflections and 143 parameters. Twelve S sites (one with half occupancy) and eighteen metal sites (5 Hg, 12 Cu and 1 Fe) occur in the crystal structure of gortdrumite. Mercury cations link two sulfur atoms in a linear coordination, Cu cations are found in various low-coordination (2, 3 and 4) sites, in agreement with the Cu preference for such environments, and Fe in tetrahedral coordination. Metal–metal interactions are also present and these contacts are discussed in relation with other copper sulfides, intermetallics and pure metals. Electron microprobe analyses of the crystal used for the structural study led to the formula Cu24.83Fe1.73Hg9.09S22.35, on the basis of 58 atoms. On the basis of information gained from the structural and chemical characterization, the crystal-chemical formula was revised to Cu24Fe2Hg9S23 (Z = 1) instead of (Cu,Fe)6Hg2S5 as reported previously. [ABSTRACT FROM AUTHOR]

The crystal structure of the mineral donharrisite, a rare nickel-mercury-sulfide reported in the literature with the formula Ni 8 Hg 3 S 9 , was solved and refined using intensity data collected from a crystal from Leogang, Salzburg Province, Austria. This study revealed that the structure is monoclinic, space group C 2/ m , with a = 11.574(3), b = 6.899(2), c = 5.419(1) Å, β = 93.71(2)° and V = 431.8(2) Å 3 . The refinement of an anisotropic model led to an R index of 0.044 for 383 independent reflections. In the crystal structure there are two Hg sites, four Ni sites and 2 S, with one Hg and one Ni site which are half-occupied. As typical of many intermetallic compounds, the donharrisite structure is characterized by atoms forming complex polyhedra as Hg[S 6 Ni 4 ], Hg[S 4 Ni 3 ], Ni[S 4 Ni 2 ], Ni[S 3 NiHg], Ni[S 6 Ni 2 Hg 2 ], Ni[S 4 Ni 3 Hg 2 ], showing exceedingly short bond distances. Electron microprobe analyses of the crystal used for the structural study led to the formula Ni 3.03 Hg 1.01 S 2.96 , on the basis of 7 atoms. On the basis of information gained from this characterization the crystal chemical formula was revised according to the structural results, yielding Ni 3 HgS 3 with Z = 4 (with a calculated density of 7.27 g/cm 3 ), instead of Ni 8 Hg 3 S 9 with Z = 2 (with a calculated density of 5.18 g/cm 3 ) as previously reported. Although neither reflection streaks nor structural disorder were observed for the selected donharrisite crystal, the possibility that the refined structure (with partially-occupied sites and exceedingly short bond distances) could be a superposition of different layers belonging to an OD (order-disorder) structure is also discussed. [ABSTRACT FROM AUTHOR]

The title mineral crystallizes in the monoclinic space group C2/m with Z = 4 (single crystal XRD). [ABSTRACT FROM AUTHOR]