New dielectric materials based on pyrochlore-type oxides- Ca3RE3Ti7Ta2O26.5 (RE = Pr, Sm, Gd, Dy or Y): Structure, FT-IR spectra, microstructure and dielectric properties

  • P. Prabhakar Rao
  • K. Ravindran Nair
  • Peter Koshy
  • V. K. Vaidyan


New dielectric materials based on complex oxides containing rare earth tantalates: Ca3RE3Ti7Ta2O26.5 (RE = Pr, Sm, Gd, Dy or Y) have been investigated for their structure, FT-IR spectra, microstructure and dielectric properties. Structural analysis using the techniques of x-ray powder diffraction coupled with fourier transform infrared spectroscopy (FT-IR) shows that the titled compounds crystallize with the cubic pyrochlore type structure. Microstructure analysis by means of scanning electron microscope exhibits that sintering the pellets at 1450C shows dense microstructure with well formed grains. The dielectric permittivity (εr) and dielectric loss (tan δ) of the pellets sintered at 1450C are found to be varying from 41-80 and 0.0715-0.0570 respectively at 100 kHz.


Oxide Microstructure Fourier Transform Rare Earth Infrared Spectroscopy 
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© Springer Science + Business Media, LLC 2006

Authors and Affiliations

  • P. Prabhakar Rao
    • 1
  • K. Ravindran Nair
    • 1
  • Peter Koshy
    • 1
  • V. K. Vaidyan
    • 2
  1. 1.Regional Research Laboratory (CSIR)ThiruvananthapuramIndia
  2. 2.Deptt. of PhysicsKerala UniversityThiruvananthapuramIndia

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