Dislocation structure and microhardness of L-arginine perchlorate single crystal

This paper presents the chemical etching and microhardness studies carried out on L-arginine perchlorate (LAPCl), a non-linear optical crystal (NLO) with a view to characterize the dislocation structure and mechanical strength of the grown crystals. LAPCl crystals employed in this investigation were grown from aqueous solution by solvent evaporation method. Optical microscopic studies of as grown habit faces revealed formation of macrosteps and valley on (100) habit face. Chemical etching of (100) face with impurity added organic solvents played an important role in the formation of etch pits. Selective etching of matched pairs on opposite faces of the same plane confirms that the pits are formed at the dislocation sites. Microhardness measurement by indentation method shows decrease of microhardness with increasing load. Nature of hardness profile is explained with the help of Meyer’s law. The work hardening index value indicates that LAPCl belongs to hard crystal category.