The crystal structure of a nonstoichiometric nasicon

Journal Article · Sat Jun 01 04:00:00 EDT 1985 · Mater. Res. Bull.; (United States)

DOI:https://doi.org/10.1016/0025-5408(85)90142-4· OSTI ID:6407209

Rudolf, F; Clearfield, A; Jorgensen, J D; Subramanian, M A

The crystal structure of a nonstoichiometric NASICON prepared from a hydrothermally synthesized precursor phase was solved by means of Xray powder and neutron powder diffraction methods. The NASICON phase is monoclinic with unit cell parameters, from Rietveld refinement of the neutron data, of a = 15.6209(8), b = 9.0326(5), c = 9.2172(5)A, ..beta.. = 123.67(1)A, V = 1082.5A/sup 3/. The space group is C2/c with Z = 4. The structure is essentially that proposed earlier by Hong, but the nonstoichiometry results from replacement of part of the Zr/sup 4 +/ by Na/sup +/. Refinement of site occupancies coupled with the requirement of overall charge balance yields the formula Na /sub 2.88/ (Na /sub 0.32/ Zr /sub 1.68/ )Si /sub 1.84/ P /sub 1.16/ O /sub 11.54/ which also agrees well with analytical data. Only 20% of the Na1 sites are occupied, but 80% of the Na3 sites are filled. This structure provides a framework from which to rationalize the many reports in the literature that NASICON can only be prepared with difficulty by high temperature solid state reactions.

• Research Organization: Department of Chemistry, Texas A and M University, College Station, Texas
• OSTI ID: 6407209
• Journal Information: Mater. Res. Bull.; (United States), Journal Name: Mater. Res. Bull.; (United States) Vol. 20:6; ISSN MRBUA
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360601* -- Other Materials-- Preparation & Manufacture
360602 -- Other Materials-- Structure & Phase Studies
ALKALI METAL COMPOUNDS
CHEMICAL COMPOSITION
CHEMICAL PREPARATION
COHERENT SCATTERING
CRYSTAL STRUCTURE
CRYSTAL-PHASE TRANSFORMATIONS
CRYSTALLOGRAPHY
DIFFRACTION
HEAT TREATMENTS
OXYGEN COMPOUNDS
PHASE STUDIES
PHASE TRANSFORMATIONS
PHOSPHORUS COMPOUNDS
PHYSICS
SCATTERING
SILICON COMPOUNDS
SODIUM COMPOUNDS
SOLID STATE PHYSICS
SYNTHESIS
TRANSITION ELEMENT COMPOUNDS
ZIRCONIUM COMPOUNDS