Structural characterization of new layered perovskites MLa2Ti2TaO10 (M = Cs, Rb) and NaLa2Ti2TaO10 · xH2O (x = 2, 0.9, 0)

Young Sik Hong, Chi Hwan Han, Keon Kim

Research output: Contribution to journalArticlepeer-review

11 Citations (Scopus)

Abstract

The crystal structures of n = 3 Dion-Jacobson phases MLa2Ti2TaO10 (M = Cs, Rb) and NaLa2Ti2TaO10 · xH2O (x = 2, 0.9, 0) have been investigated by the Rietveld analysis of their powder XRD patterns. These compounds show the new-type ordering sequence of (Ti1/2 Ta1/2) O6-TiO6-(Ti1/2Ta1/2)O6 in the tripled octahedra, corresponding to the niobium analogs of MLa2Ti2NbO10. They crystallize in the tetragonal system P4/mmm with lattice constants of a = 3.84733(9) and c = 15.4364(4) Å for CsLa2Ti2TaO10, and a = 3.8342(2) and c = 15.2776(9) Å for RbLa2Ti2TaO10. Sodium-exchanged phase was easily hydrated to NaLa2Ti2TaO10 · 2H2O, belonging to the space group I4/mmm with a = 3.8399(3) and c = 34.288(3) Å. Upon firing, NaLa2Ti2TaO10 · 2H2O was dehydrated to NaLa2Ti2TaO10 · 0.9H2O with P4/mmm at around 100°C and then NaLa2Ti2TaO10 with I4/mmm at above 200°C. The Na cations in two hydrates were surrounded with six oxygens, forming face-shared octahedra along (110) direction. These structural models, especially for the coordination environment of Na cations, were proposed for the first time.

Original languageEnglish
Pages (from-to)290-298
Number of pages9
JournalJournal of Solid State Chemistry
Volume158
Issue number2
DOIs
Publication statusPublished - 2001

Keywords

  • Dion-Jacobson phase
  • Hydrate
  • Layered perovskite
  • Ordering

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Ceramics and Composites
  • Condensed Matter Physics
  • Physical and Theoretical Chemistry
  • Inorganic Chemistry
  • Materials Chemistry

Fingerprint Dive into the research topics of 'Structural characterization of new layered perovskites MLa<sub>2</sub>Ti<sub>2</sub>TaO<sub>10</sub> (M = Cs, Rb) and NaLa<sub>2</sub>Ti<sub>2</sub>TaO<sub>10</sub> · xH<sub>2</sub>O (x = 2, 0.9, 0)'. Together they form a unique fingerprint.

Cite this