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The ?-polymorph of AgZnPO(4) with an ABW zeolite-type framework topology.

ABSTRACT: The ?-polymorph of the title compound, silver zinc orthophos-phate, was synthesized under hydro-thermal conditions. The structure consists of ZnO(4), PO(4) and AgO(4) units. The coord-ination spheres of Zn(II) and P(V) are tetra-hedral, whereas the Ag(I) atom is considerably distorted from a tetra-hedral coordination. Each O atom is linked to each of the three cations. An elliptic eight-membered ring system is formed by corner-sharing of alternating PO(4) and ZnO(4) tetra-hedra, leading to a framework with an ABW-type zeolite structure. The framework encloses channels running parallel to [100] in which the Ag cations are located, with Ag?Ag contacts of 3.099?(3)?Å. This short distance results from d(10)?d(10) inter-actions, which play a substantial role in the crystal packing. The structure of ?-AgZnPO(4) is distinct from the two other polymorphs ?-AgZnPO(4) and ?-AgZnPO(4), but is isotypic with NaZnPO(4)-ABW, NaCoPO(4)-ABW and NH(4)CoPO(4)-ABW.

SUBMITTER: Assani A

PROVIDER: S-EPMC3009017 | biostudies-other | 2010

REPOSITORIES: biostudies-other

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The γ-polymorph of AgZnPO(4) with an ABW zeolite-type framework topology.

Assani Abderrazzak A Saadi Mohamed M El Ammari Lahcen L

Acta crystallographica. Section E, Structure reports online 20101002 Pt 11

The γ-polymorph of the title compound, silver zinc orthophos-phate, was synthesized under hydro-thermal conditions. The structure consists of ZnO(4), PO(4) and AgO(4) units. The coord-ination spheres of Zn(II) and P(V) are tetra-hedral, whereas the Ag(I) atom is considerably distorted from a tetra-hedral coordination. Each O atom is linked to each of the three cations. An elliptic eight-membered ring system is formed by corner-sharing of alternating PO(4) and ZnO(4) tetra-hedra, leading to a fra ...[more]

PMID: 21588789

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