Thermally stimulated depolarization current studies of relaxation in L-asparagine monohydrate

Polycrystalline powder samples of L-asparagine monohydrate a fundamental amino acid has been studied for thermal relaxation using Thermally Stimulated Depolarizing Current (TSDC) in its normal and thermal window variations. Blank zero field TSDC, differential scanning calorimetry and x-ray diffraction studies have been performed to explore the effect of heating and cooling cycle on the sample. From the analysis of the results it has been observed that L-asparagine monohydrate undergoes irreversible phase transitions in dehydration and change in crystal structure from orthorhombic for fresh sample to monoclinic for heat-treated sample. Observed depolarization current in case of blank TSDC may be attributed to freezing of the polarization due to structural changes during heating. First TSDC Spectrum of fresh sample has been used for relaxation parameter calculations.