Crystal Structure, Dielectric Response and Thermal analysis of Ammonium Pentaborate (APB)

Nonlinear optical material Ammonium Pentaborate (APB) crystals have been grown using slow evaporation method from aqueous solution. From Powder XRD analysis the orthohrombic crystal structure was found. Various vibrations in FTIR spectrum were assigned. Thermo gravimetric analysis suggested that the crystal remained stable up to 173℃ and then decomposed through various stages and endothermic reactions were identified by DTA. The variation of dielectric constant, dielectric loss and ac conductivity with frequencies was studied at room temperature. Further investigation of dielectric properties with higher temperature is under progress.