Vibrational Analysis of Ba5−xSrxNb4O15Microwave Dielectric Ceramic Resonators

Abstract The Ba5−xSrxNb4O15ceramics have been prepared and characterised using XRD, Raman, FTIR, and microwave dielectric property measurements. The measured dielectric properties show smooth variation with Sr content. The spectroscopic studies show that the symmetry of the NbO6octahedra increases with increase in strontium content, maintaining the hexagonal structure. Hence, the possibility of a monoclinic structure for Sr5Nb4O15seems to be inappropriate. The observed symmetric stretching bands of NbO6octahedra confirm the existence of corner connected octahedra in all the solid solution compounds. The behavior of the dielectric constant of (Ba5−xSrx)Nb4O15system can be correlated to the variation of symmetric stretching vibrations of NbO6octahedra.

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