title: Crystal structure of ammonium divanadium(IV,V) tellurium(IV) hepta-oxide.
abstract: The polyhedral building blocks of the layered inorganic network in the mixed-valence title compound, (NH4)(V(IV)O2)(V(V)O2)(TeO3), are vertex-sharing V(V)O4 tetra-hedra, distorted V(IV)O6 octa-hedra and TeO3 pyramids, which are linked by V-O-V and V-O-Te bonds, forming double layers lying parallel to (100). The presumed Te(IV) lone-pairs of electrons appear to be directed inwards into cavities in the double layers. The charge-balancing ammonium cations lie between the layers and probably inter-act with them via N-H⋯O hydrogen bonds.
authors.affiliation: Department of Chemistry, University of Aberdeen, Meston Walk, Aberdeen AB24 3UE, Scotland.
authors.forename: William T A
authors.initials: WT
authors.lastname: Harrison
authors.affiliation: Department of Chemistry, University of Aberdeen, Meston Walk, Aberdeen AB24 3UE, Scotland.
authors.forename: Magnus G
authors.initials: MG
authors.lastname: Johnston
keywords: crystal structure; layered structure; lone-pair; mixed-valence; tellurium