The crystal structure of Pd3HgTe3, the synthetic analogue of temagamite

The crystal structure of the synthetic analogue of the mineral temagamite, Pd3HgTe3, was solved and refined to an R-factor of 0.0522 from single-crystal X-ray diffraction data. The structure is trigonal, space group P3m1, with a = 7.8211(6) angstrom, c = 17.281(1) angstrom, V = 917.8(1) angstrom(3) (hexagonal setting) and Z = 6. Layer modules (A-F) stacked along the c-axis form the crystal structure of Pd3HgTe3. Module A is composed of isolated octahedra [PdTe6], which share faces with adjacent octahedra from neighbouring modules. The edge-sharing [PdTe6] octahedra and [PdTe4] squares form the modules B and F, whereas the corner-sharing [PdTe4] squares constitute modules C, D and E. The Hg atoms occupy the anti-cubooctahedral voids formed by Te atoms. The Pd-Pd and Pd-Hg bonds are also present in the structure. The symmetry of temagamite was revised based on the structural results of this study.