Studies on the growth, optical, thermal and mechanical properties of l-glutamic acid hydrobromide single crystals

A semiorganic crystal, l-glutamic acid hydrobromide (LGHB), was synthesized from aqueous solution by slow evaporation technique. The lattice parameters of the grown crystal were determined using single crystal X-ray diffraction analysis. The functional groups were identified using Fourier transforms infrared spectroscopy. UV-vis-NIR spectral analysis showed excellent transparency in the visible and infrared regions. Thermo gravimetric and differential thermal analysis showed that the grown crystals are thermally stable up to 218 °C. The second harmonic generation conversion efficiency was investigated using Kurtz Perry technique. The mechanical strength of LGHB crystal was tested by Vicker's hardness tester. The grown crystal exhibits reverse indentation size effect (RISE) as the hardness value increases with increase in load. The elastic stiffness constant is calculated from the hardness value.