• A L Shashi Mohan

      Articles written in Bulletin of Materials Science

    • Structural and dielectric studies of some niobate-titanate systems

      A M Varaprasad A L Shashi Mohan D K Chakrabarty A B Biswas

      More Details Abstract Fulltext PDF

      Ferroelectric ceramics of the general formulax (Li1/2 La1/2 TiO3) (1−x) (LiNbO3) have been found to have tungsten bronze (TTB) and ilmenite type structure in the ranges 0·8≤x≤1·0 and 0≤x≤0·2 respectively. The system is biphasic in the other ranges. All single phase materials exhibit dielectric anomalies in the temperature range 300–600 K. The high dielectric constant of the TTB phase is explained as due to the existence of localised rotational excitons arising from a large number of defect structural units and their coupling with one of the low frequency lattice modes. Information about the lattice modes to which the rotational excitons are coupled has been obtained from Raman spectra.

  • Bulletin of Materials Science | News

    • Editorial Note on Continuous Article Publication

      Posted on July 25, 2019

      Click here for Editorial Note on CAP Mode

© 2017-2019 Indian Academy of Sciences, Bengaluru.