“…Thus, it is urgent to exploit microwave dielectric ceramic materials with appropriate permittivity (ε r ) to meet the requirements of equipment application, high quality factor (Q × f), nearzero temperature coefficient of resonant frequency (TCF) and low sintering temperature (S.T.). [8][9][10] In recent years, many Mo-based ABO 4 compounds with scheelite structure have received much interest because they have low S.T., high microwave dielectric properties, and high tolerance to structural adjustment, [11][12][13][14] such as (Na 0.5 Ln 0.5 )MoO 4 (where Ln is = Ce, La, or Nd), 15,16 (Li 0.5 Ln 0.5 )MoO 4 (where Ln = is Ce, Y, Sm, Nd, Gd, Er, or Yb), 17 (A 1/2 Bi 1/2 )MoO 4 (where A = is Rb, Na, Ag, K, or Li). 18 Mo-based ABO 4 ceramics have been reported with low or medium dielectric constants, and most of them could crystalize as tetragonal scheelite phase.…”