Crystal chemistry of the M₁^1+,2+-M₂^2+,3+-(H)-arsenites

Autor(en)

Tamara Đorđević

Abstrakt

The crystal structures among M1-M2-(H)-arsenites (M1 = Li+, Na+, K+, Rb+, Cs+, Ca2+, Sr2+, Ba2+, Cd2+, Pb2+; M2 = Mg2+, Mn2+,3+, Fe2+,3+, Co2+, Ni2+, Cu2+, Zn2+) are less investigated. Up to now, only the structure of Pb3Mn(AsO3)2(AsO2OH) was described. The crystal structure of hydrothermally synthesized Na4Cd7(AsO3)6 was solved from the single-crystal X-ray diffraction data. Its trigonal crystal structure [space group Requation image, a = 9.5229(13), c = 19.258(4) Å, ? = 120°, V = 1512.5(5) Å3, Z = 3] represents a new structure type. The As atoms are arranged in monomeric (AsO3)3- units. The surroundings of the two crystallographically unique sodium atoms show trigonal antiprismatic coordination, and two mixed Cd/Na sites are remarkably unequal showing tetrahedral and octahedral coordinations. Despite the 3D connection of the AsO3 pyramids, (Cd,Na)Ox polyhedra and NaO6 antiprisms, a layer-like arrangement of the Na atoms positioned in the hexagonal channels formed by CdO4 deformed tetrahedra and AsO3 pyramids in z = 0, 1/3, 2/3 is to be mentioned. These pseudo layers are interconnected to the 3D network by (Cd,Na)O6 octahedra. Raman spectra confirmed the presence of isolated AsO3 pyramids.

Organisation(en)

Institut für Mineralogie und Kristallographie

Journal

Zeitschrift für Anorganische und Allgemeine Chemie

Band

641

Seiten

1863-1868

Anzahl der Seiten

6

ISSN

0044-2313

DOI

https://doi.org/10.1002/zaac.201500252

Publikationsdatum

07-2015

Peer-reviewed

Ja

ÖFOS 2012

104011 Materialchemie, 105113 Kristallographie, 104024 Röntgenstrukturanalyse

Schlagwörter

ASJC Scopus Sachgebiete

Inorganic Chemistry

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/crystal-chemistry-of-the-m112m223harsenites(e983ebeb-6ab8-4390-9c4a-07e656d64330).html