Microwave X-band permittivity measurements on 12-tungstophosphoric acid hexahydrate
Abstract Complex permittivity measurements of 12-tungstophosphoric acid hexahydrate (WPA·6H 2 O) have been performed in the X-band region at room temperature. Permittivity data were obtained by measuring reflection ( S 11 ) and transmission ( S 21 ) parameters with a network analyzer and also by using a short-circuited-waveguide. Results on powder samples are compared with the results on compressed samples using the model of mixtures. From Cole–Cole plots, a dipole relaxation time τ =1.9×10 −11 s was determined and attributed to polyatomic ion reorientation.