AgPb
2B
2V
3O
12 (B = Mg, Zn) ceramics with low sintering temperature were synthesized via the conventional solid-state reaction route. Rietveld refinements of the X-ray diffraction patterns confirm cubic symmetry with space group . The number of observed vibrational modes and those predicted by group theoretical calculations also confirm the space group
. At the optimum sintering temperature of 750°C/4 hours, AgPb
2Mg
2V
3O
12 has a relative permittivity of 23.3 ± 0.2, unloaded quality factor () of 26 900 ± 500 GHz (), and temperature coefficient of resonant frequency of 19.3 ± 1 ppm/°C, while AgPb
2Zn
2V
3O
12 has the corresponding values of 26.4 ± 0.2, 28 400 ± 500 GHz () and –18.4 ± 1 ppm/°C at 590°C/4 hours. Microwave dielectric properties of a few reported garnets and Pb
2AgB
2V
3O
12 (B = Mg, Zn) ceramics were correlated with their intrinsic characteristics such as the Raman shifts as well as width of A
1g Raman bands. Higher quality factor was obtained for lower full width at half-maxima (FWHMs) values of A
1g modes. The increase in B-site bond valence contributes to high and low |
τf| with the substitution of Zn
2+ by Mg
2+. Furthermore, the high ionic polarizability and unit cell volume with Zn
2+substitution contribute to increased relative permittivity.
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