Growth and characterization of pure and doped nonlinear optical l‐arginine acetate single crystals

Single crystals of organic nonlinear optical material of pure, Cu²⁺ and Mg²⁺ doped L‐arginine acetate (LAA) were successfully grown by slow evaporation method at room temperature. The UV‐Vis‐NIR spectra of pure and doped LAA indicate that these crystals possess a wide optical transmission window from 240‐1600 nm. Non‐linear optical studies reveal that the SHG efficiency of LAA is nearly three times that of KDP. The dielectric response of the samples was studied in the frequency region 100 Hz to 2 MHz and the influence of Cu²⁺ and Mg²⁺ substitution on the dielectric behaviour had been investigated. Photoconductivity study proves that both pure and Cu²⁺ and Mg²⁺ doped LAA crystal exhibit positive photoconductivity. It is evident from the Vickers hardness study that the hardness of the crystal decreases with increasing load both for pure and doped samples. ESR studies confirmed the incorporation of Cu²⁺ into LAA and the value of g‐factor was found to be 2.1654. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)