Investigation on Thermal, Optical, Second Order and Third Order NLO Properties of a Nonlinear Optical Single Crystal of L-Leucinium Hydrogen Maleate (LLM)

A Hemalatha (1) , S Senthil (1)

1 Department of Physics, Government Arts College for Men (Autonomous), Chennai

Organic Nonlinear optical (NLO) single crystals of L-Leucinium Hydrogen Maleate (LLM) have been grown by the slow evaporation solution growth technique at room temperature. The X-Ray diffraction studies proved that the LLM crystals belong to monoclinic system with noncentrosymmetric space group (C2). The decomposition and thermal strength of the LLM crystals were established by TGA/DTA studies. UV-vis-NIR absorption study shows good transparency of the LLM crystal and the lower cutoff wavelength was found to be 212 nm. The optical band gap, reflectance, refractive index and electrical susceptibility were also calculated. Second order efficiency of the LLM crystal was determined using Kurtz and Perry powder technique. Third order nonlinear studies were performed using Z-Scan technique. Nonlinear parameters such as nonlinear refractive index, absorption coefficient, and nonlinear optical susceptibility were evaluated for the LLM crystal. Introduction. Amino acid is one of the rich choice for NLO material because of its coherent blue green laser generation and frequency doubling applications. Amino acids are promissing candidate for its chirality, weak vanderwaals and hydrogen bonds, the absence of strongly conjugated bonds, wide transparency, bands in the visible and UV spectral regions and zwitter ionic nature of the molecule which is important for crystal hardness [1]. In the crystal engineering and supramolecular point of views L-Leucine is an interesting molecule compared to other amino acid materials and it is an essential branched chain of alpha amino acid [2]. Many optically active aminoacids show highly efficient second harmonic generation. Maleic acid forms crystalline maleate of various organic molecules through hydrogen bonding and π-π interactions. In maleic acid the intramolecular hydrogen bond is very strong and has large π-conjugation has attracted our attention [3]. In this paper, it is reported on growth of L-Leucinium Hydrogen Maleate (LLM) single crystal followed by characterizations like XRD, TG-DTA, UV-Vis-NIR and NLO studies are discussed in detail.

Mots clés: XRD studies; TGA – DTA; NLO efficiency; absorption spectral analysis; Z-Scan studies

Domaines: Matériaux

A Hemalatha, S Senthil. Investigation on Thermal, Optical, Second Order and Third Order NLO Properties of a Nonlinear Optical Single Crystal of L-Leucinium Hydrogen Maleate (LLM) . Mechanics, Materials Science & Engineering MMSE Journal. Open Access, 2017, 9, ⟨10.2412/mmse.1.75.798⟩. ⟨hal-01503802⟩