The Library
Structural characterisation of ferroelectric Ag2Nb4O11 and dielectric Ag2Ta4O11
Tools
Tools
Tools
Masó, Nahum, Woodward, David I., Thomas, Pam A., Várez, Alejandro and West, Anthony R. (2011) Structural characterisation of ferroelectric Ag2Nb4O11 and dielectric Ag2Ta4O11. Journal of Materials Chemistry, Vol.21 (No.8). pp. 2715-2722. doi:10.1039/c0jm02540b
Research output not available from this repository, contact author.
Official URL: http://dx.doi.org/10.1039/C0JM02540B
Abstract
Structural characterisation of Ag2Nb4O11 and Ag2Ta4O11 powders has been carried out by Rietveld refinement of neutron powder diffraction data in the temperature range 10–573 K, symmetry-adapted mode analysis and second-harmonic generation. Ag2Nb4O11 ceramics appear to be ferroelectric with a maximum permittivity of 150 at TC ≈ 400 K, frequency-independent permittivity below this temperature and a shoulder in the ε′ vs. temperature profile at 200 K. The space group changes from R3c to R3c as the temperature decreases through TC with a further transition from R3c to R3 below 200 K. The origin of the polar structure is related to displacement of Nb atoms in pentagonal bipyramids towards apical oxygens and in octahedra towards faces. This displacement towards octahedra faces is observed for some Ag atoms too. Ag2Ta4O11 ceramics show temperature-independent permittivity of 20, with a centrosymmetric crystal structure, R3c. Comments on possible phase transition(s) of several compounds similar to Ag2(Nb,Ta)4O11 are made.
| Item Type: | Journal Article | ||||
|---|---|---|---|---|---|
| Subjects: | Q Science > QC Physics Q Science > QD Chemistry |
||||
| Divisions: | Faculty of Science > Physics | ||||
| Library of Congress Subject Headings (LCSH): | Ferroelectricity, Dielectrics, Electrical ceramics, Ferroelectric ceramics | ||||
| Journal or Publication Title: | Journal of Materials Chemistry | ||||
| Publisher: | Royal Society of Chemistry | ||||
| ISSN: | 0959-9428 | ||||
| Official Date: | 2011 | ||||
| Dates: |
|
||||
| Volume: | Vol.21 | ||||
| Number: | No.8 | ||||
| Number of Pages: | 7 | ||||
| Page Range: | pp. 2715-2722 | ||||
| DOI: | 10.1039/c0jm02540b | ||||
| Status: | Peer Reviewed | ||||
| Publication Status: | Published | ||||
| Access rights to Published version: | Restricted or Subscription Access | ||||
| Funder: | Engineering and Physical Sciences Research Council (EPSRC) |
Data sourced from Thomson Reuters' Web of Knowledge
Request changes or add full text files to a record
Repository staff actions (login required)
 |
View Item |
