Gamma and neutron irradiation effects on the structural and optical properties of potash alum crystals

•The effect of irradiation on potash alum crystals has been studied.•Changes in structural parameter are attributed to deformation of the structure.•Optical band gap increases considerably with neutron irradiation.

The effects of gamma and neutron irradiation on the structural and optical properties have been presented in this article. The potash alum crystals were grown by the slow evaporation technique. The crystals were then exposed with 60Co gamma rays and Am-Be neutron source. The radiation induced effects were analysed using XRD, UV-visible techniques. The refractive index was determined by the Brewster's angle method. There has been an increase in the diffraction peak intensity with the increase in irradiation doses, which indicates an increase in crystalline perfection of crystals. There has been a marginal change in dislocation density, micro strain and distortion parameter, which is attributed to deformation of the structure due to irradiation. The UV visible study reveals a shift in transparency cut off wavelength towards lower wavelength up to 70 kGy of gamma dose and this has resulted in an increase in optical band gap energy with increase in gamma dose. There is a considerable increase in the optical band gap after five hour neutron irradiation.