Studies on Dielectric Properties of ADP Crystals

Abstract

Ammonium dihydrogen phosphate (NH4HPO4, ADP) is an excellent inorganic nonlinear optical material with different device applications. The present work is based on the pure ADP crystals that is successfully grown from aqueous solution by slow evaporation technique at room temperature. The grown crystals are subjected to various characterizations like XRD, and dielectric studies. The crystalline nature and tetragonal structure of the grown crystals having lattice parameters are observed by powder X-ray diffraction analysis. The dielectric properties such as dielectric constant and dielectric loss for the crystals at different areas are studied as a function of frequency in the range 50 kHz to 5 MHz at room temperature. It is found that the dielectric permittivity decreased exponentially at lower frequency region up to 1 kHz and then the dielectric permittivity remains constant at higher frequency region as the frequency increased. It is observed that as area of ADP crystal increases the dielectric constant increases and for area of 42 mm2 the dielectric constant value is high among all the different areas of ADP crystals. © 2019 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim