title: Structure of the new mineral sarrabusite, Pb5CuCl4(SeO3)4, solved by manual electron-diffraction tomography.
abstract: The new mineral sarrabusite Pb(5)CuCl(4)(SeO(3))(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 CuO(4)Cl(2) and PbO(8) polyhedra parallel to the c axis, which share corners laterally with two zigzag corner-sharing chains of PbO(6)Cl(2) and PbO(4)Cl(4) bicapped trigonal prisms. These blocks are linked together by SeO(3)(2-) flat-pyramidal groups.
authors.affiliation: Center for Nanotechnlogy Innovation@NEST, Istituto Italiano di Tecnologia, Piazza S. Silvestro 12, I-56127 Pisa, Italy. mauro.gemmi@iit.it
authors.forename: Mauro
authors.initials: M
authors.lastname: Gemmi
authors.forename: Italo
authors.initials: I
authors.lastname: Campostrini
authors.forename: Francesco
authors.initials: F
authors.lastname: Demartin
authors.forename: Tatiana E
authors.initials: TE
authors.lastname: Gorelik
authors.forename: Carlo Maria
authors.initials: CM
authors.lastname: Gramaccioli