Dielectric Properties of New Cd1-3xDy2x[]xMoO4 Molybdates (where 0 < x ≤ 0.2)
New scheelite type Cd1-3xDy2x[]xMoO4solid solution, where 0.0098 ≤ x ≤ 0.2 and [] denotes the cationic vacancies, was investigated by using UV-vis-NIR and dielectric spectroscopies at room temperature and in the temperature range 77-400 K, respectively. These studies showed the optical band gap energy Eg above 3.4 eV and relative low dielectric permittivity: εr ~ 6.0, 9.5, 7.0 and 8.2 for the x parameter 0.0098, 0.0839, 0.1667 and 0.2000, respectively. εr slightly decreases with increasing frequency and slightly increases at higher temperatures. All samples showed the maximum permittivity in the temperature range of 250-350 K. The loss tangent exhibited similar behaviour and its maximum value did not exceed 0.25. These results are discussed in a context of the shallow trap levels and the Maxwell-Wagner model.