DEFECT STRUCTURE FERROELECTRICS (DIELECTRIC AND STRUCTURAL INVESTIGATIONS OF FERROELECTRICS POSSESSING DEFECT STRUCTURES).

Abstract

The dielectric and X-ray structural properties of the system NaNb03-Sr0.5Nb03 were determined from the end member NaNb03 to the limit of the solid solution at Na0.50Sr0.25Nb03. A ferroelectric phase was found to exist in this system beyond a concentration of 10 mole percent of SrNb206. No distinct morphotropic phase boundary between this ferroelectric phase and the antiferroelectric phase of NaNb03 was observed. The crystalline symmetry of the perovskite sub-cell of pure NaNb03 was determined as a function of temperature using CuK (alpha) radiation. The sub-cell symmetries of the compositions studied in the system were determined as functions of temperature. It was determined that the ferroelectric phase in this system possesses a multiple cell perovskite structure which is related to the antiferroelectric structure of pure NaNb03. The weak superstructure lines exhibited in the X-ray patterns of NaNb03 and these solid solutions vanished when the perovskite sub-cell edge attained a value of 3.941A.

Document Details

Document Type
Technical Report
Publication Date
Jun 20, 1964
Accession Number
AD0601675

Entities

People

  • V. J. Tennery

Organizations

  • University of Illinois Urbana–Champaign

Tags

DTIC Thesaurus Topics

  • Boundaries
  • Electromagnetic Radiation
  • Ionizing Radiation
  • Perovskites
  • Radiation
  • Solid Solutions
  • Structural Properties
  • Superstructures
  • Symmetry
  • X Rays

Fields of Study

  • Physics

Readers

  • Materials Science and Engineering.
  • Munitions and Ordnance Engineering