Commensurate and incommensurate structures of the hexabromotellurate(IV) bis {dibromodiselenate(I)} ion - [(C2H5)(n)(C6H5)(4-n)P](2)[TeBr6(Se2Br2)(2)], n=0,1

Investor logo
Investor logo

Warning

This publication doesn't include Faculty of Arts. It includes Faculty of Science. Official publication website can be found on muni.cz.
Authors

JANICKIS Vitalijus NEČAS Marek NOVOSAD Josef DUŠEK Michal PETŘÍČEK Václav

Year of publication 2002
Type Article in Periodical
Magazine / Source Acta Crystallographica Section B-Structural Science
MU Faculty or unit

Faculty of Science

Citation
Field Inorganic chemistry
Keywords CRYSTAL-STRUCTURES; SALTS
Description Structure analysis of [(C2H5)(n)(C6H5)(4-n)P](2)[TeBr6(Se2Br2)(2)] is presented for n=1 and 0 [ hereafter (I) and (II)]. Crystal (I) has been synthesized from elemental selenium, tellurium tetrabromide, ethyltriphenylphosphonium bromide and bromine. It has a standard monoclinic structure, space group P2(1)/c, and has been solved and refined to R=0.0357 for 4803 observed X-ray reflections by traditional techniques. Crystal (II), which has been prepared from elemental selenium, tellurium tetrabromide, tetraphenylphosphonium bromide and bromine, is an incommensurately one-dimensionally modulated structure with planar monoclinic superspace group. (II) has been refined to R=0.0501 for 4247 observed reflections. The modulation of the atoms that belong to the anion switches between two different basic positions, which are described by the crenel function algorithm. The modulation of the phenyl groups is much weaker and it could be refined within the rigid-body approximation. The TeBr6 octahedron is nearly regular in both structures. The two Br atoms of the octahedron have a bond to one of the Se atoms in an Se2Br2 molecule. For (I) both bonded Br atoms are trans positioned, while for (II) they can be either trans or cis positioned. The alternations of those arrangements are caused by modulation. The point group of the anion is -1 for crystal (I) and 2/m for the average structure of crystal (II).
Related projects:

You are running an old browser version. We recommend updating your browser to its latest version.