S.Lincy Mary Ponmani, P.Selvarajan, N.Balasundari
The title compound, Bis ß-alanine urea (BBAU) was synthesized from aqueous solutions of ß-alanine and urea taken in 2:1 molar ratio. The crystal reached a maximum size of 23 mm x 18 mm x 6 mm in a period of 15 days. It is observed that the grown crystal is well formed with sharp edges. Single crystals of ß-alanine have been subjected to X-ray diffraction analysis to determine the crystal structure. The single crystal XRD data of BBAU shows that the cell constants a=6.124(3) Å, b=9.959(5) Å, c=13.967 (8) Å and a=90°, ß=90 °, ?=90° and volume of the unit cell is 851.83 (2) Å3. It belongs to orthorhombic crystal system. Fourier Transform Infrared spectral measurements have been carried out on the grown crystals in order to identify the functional groups. Optical transparency of the grown crystals was investigated by UV–Vis–NIR spectrum. The lower optical cutoff wavelength for this crystal was observed at 235 nm. The band gap value is calculated from the cut-off wavelength and is found to be 5.27 eV.Mechanical hardness studies reveal that Vickers hardness number steeply increases as the load increases for the crystal. The dielectric constant and dielectric loss decrease with frequency and increase with temperature. The activation energies were calculated for the crystal.
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