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Structural characterization of quaternary selenites of tungsten(VI), A ₂W₃SeO₁₂ (A = NH₄, Cs, Rb, K or Tl).

ABSTRACT: The quaternary A ₂W₃SeO₁₂ (A = NH₄, Cs, Rb, K or Tl) selenites have been prepared in the form of single crystals by hydro-thermal and novel solid-state reactions. They were characterized by X-ray diffraction, thermal and spectroscopic studies. All of them have a hexa-gonal tungsten oxide (HTO) related [W₃SeO₁₂]^2- anionic framework with pyramidally coordinated Se⁴⁺ ions. The known A ₂W₃SeO₁₂ (A = NH₄, Cs or Rb) compounds are isostructural with the Cs₂W₃TeO₁₂ compound and have a non-centrosymmetric layered structure containing intra-layer Se-O bonds. The new compound K₂W₃SeO₁₂(α) is isostructural with the K₂W₃TeO₁₂ compound and has a centrosymmetric three-dimensional structure containing inter-layer Se-O bonds. It is inferred that the new Tl₂W₃SeO₁₂ compound has the same three-dimensional structure as K₂W₃SeO₁₂(α).

SUBMITTER: Balisetty V

PROVIDER: S-EPMC8025859 | biostudies-literature |

REPOSITORIES: biostudies-literature

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