Synthesis,infrared and X-ray diffraction studies of mixed halogen sodalites and sodalites containing silver derivatives

摘要

Low temperature hydrothermal technique has been employed for the synthesis of different mixed halogen sodalites of the type Na8[AlSiO4]6Cl_(2_x)Brx and Na8 [AlSiO4]6Br_(2-x)Ix (0<= x <2).The competition between chloride,bromide and iodide is also studied for the formation of mixed sodalites.Infrared spectroscopy has been used successfully for the confirmation of the framework structure and dopant.Significant IR frequency changes are observed in the region of 300-1200 cm-1 for symmetric,asymmetric and bending modes of vibration.This IR shift is found to be dependent on sample preparation.X-ray powder diffraction is used to establish the structure of mixed halogen sodalites.Further,silver containing derivatives,Na_(8-x)Ag_x[AlSi04]6(MnO4)2 and Na_(8-x)Ag_x[AlSiO4]6(ClO4)2,are also obtained through aqueous ion exchange process.A relationship has been established between the amount of silver exchanged with IR frequency of asymmetric mode of vibration.