Published December 2004 | Version v1
Journal article

A structure, conductivity and dielectric properties investigation of A3CoNb2O9 (A=Ca2+, Sr2+, Ba2+) triple perovskites

  • 1. Research School of Chemistry, Australian National University, Solid State Structural Chemistry, Canberra, ACT 0200 (Australia)
  • 2. Research School of Chemistry, The Australian National University, Solid State Structural Chemistry, Canberra, ACT 0200 (Australia)
  • 3. Bragg Institute, Australian Nuclear Science and Technology Organisation, PMB 1, Menai NSW 2234 (Australia)
  • 4. Institute of Environmental Science and Engineering, Nanyang Technological University (NTU), Innovation Centre Block 2, Unit 247, 18 Nanyang Drive, Singapore 637723 (Singapore)

Description

The room temperature structures as well as the temperature-dependent conductivity and dielectric properties of the A3CoNb2O9 (A=Ca2+, Sr2+ and Ba2+) triple perovskites have been carefully investigated. A constrained modulation wave approach to Rietveld structure refinement is used to determine their room temperature crystal structures. Correlations between these crystal structures and their physical properties are found. All three compounds undergo insulator to semiconductor phase transitions as a function of increasing temperature. The hexagonal Ba3CoNb2O9 compound acts as an insulator at room temperature, while the monoclinic Ca3CoNb2O9 compound is already a semiconductor at room temperature. The measured dielectric frequency characteristics of the A=Ba compound are excellent

Additional details

Identifiers

DOI
10.1016/j.jssc.2004.09.016;
PII
S0022-4596(04)00514-6;

Publishing Information

Journal Title
Journal of Solid State Chemistry
Journal Volume
177
Journal Issue
12
Journal Page Range
p. 4428-4442
ISSN
0022-4596
CODEN
JSSCBI

Optional Information

Copyright
Copyright (c) 2004 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.