Download citation
Download citation
link to html
The new mineral sarrabusite Pb5CuCl4(SeO3)4 has been discovered in the Sardinian mine of Baccu Locci, near Villaputzu. It occurs as small lemon-yellow spherical aggregates of tabular crystals (< 10 µm) of less than 100 µm in diameter. The crystal structure has been solved from and refined against electron diffraction of a microcrystal. Data sets have been measured by both a manual and an automated version of the new electron-diffraction tomography technique combined with the precession of the electron beam. The sarrabusite structure is monoclinic and consists of (010) layers of straight chains formed by alternating edge-sharing CuO4Cl2 and PbO8 polyhedra parallel to the c axis, which share corners laterally with two zigzag corner-sharing chains of PbO6Cl2 and PbO4Cl4 bicapped trigonal prisms. These blocks are linked together by SeO_3^{2-} flat-pyramidal groups.

Supporting information

cif

Crystallographic Information File (CIF) https://doi.org/10.1107/S010876811104688X/dk5002sup1.cif
Contains datablocks global, I

hkl

Structure factor file (CIF format) https://doi.org/10.1107/S010876811104688X/dk5002Isup2.hkl
Contains datablock I

Computing details top

Data collection: QED (Belletti, Calestani, Gemmi, Migliori, Ultramicroscopy, 2000, 81, 57-65); cell refinement: UNITCELL (Holland, Redfern, (1997). Mineralogical Magazine, 61, 65-77. ); program(s) used to solve structure: SIR2008 (Burla, Caliandro, Camalli, Carrozzini, Cascarano, De Caro, Giacovazzo, Polidori, Siliqi, Spagna, R (2007). J. Appl. Cryst. 40, 609-613); program(s) used to refine structure: ? Petricek, V., Dusek, M. & Palatinus L. (2006). Jana2006. Structure Determination Software Programs. Institute of Physics, Praha, Czech Republic..

(I) top
Crystal data top
Cl4CuO12Pb5Se4β = 101.77 (1)°
Mr = 1749.19V = 1912.8 (5) Å3
Monoclinic, C2/cZ = 4
Hall symbol: -C 2ycF(000) = 2956
a = 24.917 (3) ÅDx = 6.072 Mg m3
b = 5.506 (1) ÅElectron radiation, λ = 0.0251 Å
c = 14.242 (2) ÅT = 293 K
Data collection top
FEI TECNAI F20ST
diffractometer
Rint = 0.255
Radiation source: field emission electron gunθmax = 0.8°, θmin = 0.1°
manual diffraction tomography scansh = 2727
2614 measured reflectionsk = 66
915 independent reflectionsl = 1414
914 reflections with I > 3σ(I)
Refinement top
Refinement on F43 parameters
R[F2 > 2σ(F2)] = 0.3070 restraints
wR(F2) = 0.4155 constraints
S = 26.69Weighting scheme based on measured s.u.'s w = 1/(σ2(F) + 0.0001F2)
915 reflections(Δ/σ)max = 0.020
Special details top

Experimental. Structure solved by electron diffraction data collected with manual and automated diffrraction tomography. Microscope used: manual diffraction tomography FEI TECNAI F20ST (200 kV),

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Pb10.1059 (3)0.0639 (14)0.1742 (8)0.031 (3)*
Pb20.2686 (3)0.0123 (13)0.3721 (9)0.031 (3)*
Pb300.562 (2)0.250.031 (3)*
Se10.1626 (6)1.508 (2)0.3293 (15)0.019 (3)*
Se20.0461 (6)0.003 (2)0.4147 (15)0.019 (3)*
Cu100.50.50.020 (5)*
Cl10.2971 (11)0.490 (4)0.456 (3)0.037 (5)*
Cl20.1203 (11)0.507 (4)0.534 (3)0.037 (5)*
O10.1810 (15)0.730 (7)0.270 (4)0.019 (4)*
O20.0641 (15)0.932 (7)0.309 (4)0.019 (4)*
O30.1886 (14)0.247 (7)0.285 (4)0.019 (4)*
O40.0067 (15)0.263 (6)0.382 (4)0.019 (4)*
O50.0173 (14)0.807 (6)0.404 (4)0.019 (4)*
O60.1033 (15)0.430 (7)0.254 (4)0.019 (4)*
Bond lengths (Å) top
Pb1—Cl1i3.36 (4)Pb3—O52.69 (5)
Pb1—Cl2ii3.16 (3)Pb3—O5iv2.69 (5)
Pb1—O1iii2.77 (4)Pb3—O62.67 (4)
Pb1—O2iii2.47 (5)Pb3—O6iv2.67 (4)
Pb1—O32.54 (4)Se1—Cl2vii3.29 (5)
Pb1—O4iv2.96 (4)Se1—O1vii1.61 (5)
Pb1—O5v2.67 (4)Se1—O2vii3.36 (4)
Pb1—O62.32 (4)Se1—O3vii1.74 (4)
Pb2—Cl1iii3.14 (3)Se1—O6vii1.69 (4)
Pb2—Cl12.91 (3)Se2—O2iii1.70 (6)
Pb2—Cl1vi3.21 (4)Se2—O41.75 (4)
Pb2—Cl2vi2.82 (3)Se2—O5iii1.89 (4)
Pb2—O1iii2.83 (4)Se2—O5viii3.00 (5)
Pb2—O1i2.85 (5)Cu1—Cl22.94 (3)
Pb2—O32.48 (4)Cu1—Cl2viii2.94 (3)
Pb2—O3i3.04 (5)Cu1—O42.17 (5)
Pb3—O22.62 (4)Cu1—O4viii2.17 (5)
Pb3—O2iv2.62 (4)Cu1—O52.16 (4)
Pb3—O42.48 (5)Cu1—O5viii2.16 (4)
Pb3—O4iv2.48 (5)
Symmetry codes: (i) x+1/2, y1/2, z+1/2; (ii) x, y+1, z1/2; (iii) x, y1, z; (iv) x, y, z+1/2; (v) x, y1, z+1/2; (vi) x+1/2, y+1/2, z+1; (vii) x, y+1, z; (viii) x, y+1, z+1.
 

Follow Acta Cryst. B
Sign up for e-alerts
Follow Acta Cryst. on Twitter
Follow us on facebook
Sign up for RSS feeds