• G Bhagavannarayana

      Articles written in Bulletin of Materials Science

    • Synthesis, growth, optical, mechanical and electrical properties of 𝐿-lysine 𝐿-lysinium dichloride nitrate (𝐿-LLDN) single crystal

      V Vasudevan R Ramesh Babu A Reicher Nelcy G Bhagavannarayana K Ramamurthi

      More Details Abstract Fulltext PDF

      Semi-organic nonlinear optical material, 𝐿-lysine 𝐿-lysinium dichloride nitrate (2C6H15N2O$^{+}_{2}$.H+.NO$^{-}_{3}$.2Cl-) was synthesized at room temperature. Single crystals of 𝐿-LLDN were grown by slow cooling solution growth technique. The grown crystal was confirmed by powder X-ray diffraction analysis. The crystalline perfection of the grown single crystal was characterized by high-resolution X-ray diffraction (HRXRD) studies. The cut-off wavelength was determined by UV-vis transmission spectral analysis. The frequency doubling of the grown crystal was confirmed by powder second harmonic generation (SHG) measurement. The refractive index and birefringence of the crystal were determined using He–Ne laser source. Mechanical property of the crystal was determined by Vickers hardness tester. The frequency and temperature dependence of dielectric constant (𝜀r), dielectric loss (tan 𝛿) and a.c. conductivity (𝜎ac) were also measured.

    • Studies on bulk growth, structural and microstructural characterization of 4-aminobenzophenone single crystal grown from vertical Bridgman technique

      S P Prabhakaran R Ramesh Babu G Bhagavannarayana K Ramamurthi

      More Details Abstract Fulltext PDF

      Bulk single crystal of 4-aminobenzophenone with a size of 25 mm dia. and 35 mm length has been grown by vertical Bridgman technique. The crystal system of the grown crystal was confirmed by X-ray diffraction analysis. Crystalline perfection was analysed by high resolution X-ray diffraction studies. Chemical etching was carried out for the first time in 4-aminobenzophenone single crystal to study the defects presented in the grown crystal and the growth mechanism involved. Several organic etchants were employed with different etching time to select suitable etchant for studying dislocation pattern and other structural defects existing in the grown crystal. Etch patterns such as spirals and striations observed for the selective etchants provide considerable information on growth mechanism of the crystal.

  • Bulletin of Materials Science | News

    • Dr Shanti Swarup Bhatnagar for Science and Technology

      Posted on October 12, 2020

      Prof. Subi Jacob George — Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bengaluru
      Chemical Sciences 2020

      Prof. Surajit Dhara — School of Physics, University of Hyderabad, Hyderabad
      Physical Sciences 2020

    • Editorial Note on Continuous Article Publication

      Posted on July 25, 2019

      Click here for Editorial Note on CAP Mode

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