Studies on thermophysical and mechanical properties of hydrazonium l-tartrate An organic nonlinear optical material

• Published in: Journal of thermal analysis and calorimetry Vol. 116; no. 1; pp. 339 - 347
• Main Authors: Kannan, V., Rakhikrishna, R., Philip, J., Brahadeeswaran, S.
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01.04.2014; Springer
• Subjects: Analytical Chemistry; Calorimetry; Chemistry; Chemistry and Materials Science; Inorganic Chemistry; Measurement Science and Instrumentation; Physical Chemistry; Polymer Sciences; DTA; TG; PPE; DSC; Microhardness
• ISSN: 1388-6150; 1588-2926
• DOI: 10.1007/s10973-013-3444-1

Bulk single crystals of hydrazonium l -tartrate (HLT) an organic nonlinear optical material have been grown by isothermal solvent evaporation method using water:methanol (5:1) as solvent. The title compound crystallizes in orthorhombic system with noncentrosymmetric space group P 2 1 2 1 2 1 . The thermal stability, thermal decomposition, and specific heat capacity of HLT have been explored by thermogravimetric/differential thermal analysis, differential scanning calorimetric analysis and modulated differential scanning calorimetric analysis. Improved photopyroelectric technique was adapted to analyze the most important thermophysical parameters in heat transfer calculations such as thermal effusivity, thermal diffusivity, thermal conductivity and heat capacity of HLT single crystal. The measured specific heat of HLT obtained from single crystal sample at 300 K is found to be about 3875 J kg −1  K −1 suggesting that the HLT could possesses high optical damage value and will be useful for the fabrication of optical devices. The anisotropic mechanical behaviors of HLT have been tested on crystallographic planes (100), (010), and (001) using Vickers microhardness tester at room temperature and the results were analyzed through classical Mayer’s law. Room temperature Vickers microhardness test reveals that hardness number of HLT are significantly different in measured orientations and interestingly (100), (001) orientations of HLT belong to soft material category, while the (010) belongs to hard material category because of Van der Waals forces. All these studies have been performed for the first time and aimed to explore the useful and safe regions of thermal and mechanical properties to enhance its usefulness for device fabrications.