Dielectric constants of YVO_4, Fe-, Ge-, and V-containing garnets, the polarizabilities of Fe_2O_3, GeO_2, and V_2O_5, and the oxide additivity rule

The dielectric constants and dissipation factors of Y_3Fe-5O_(12) , YVO_4 , NaCa_2Mg_2V_3O_(12), and a variety of Ge garnets were determined at 1 MHz using a two-terminal method and empirically determined edge corrections. The results are: Y_3Fe_5O_(12) K'=15.70 tan δ = 0.0009 Ca_3Ga_2Ge_3O_(12) K'=9.73 tan δ = 0.0007 Ca_(.90) Y_(1.88)Mg_(2.27)Ge_3O_(12) K'=10.35 tan δ = 0.0006 CaY_(1.96)Nd_(.04)Zn_2Ge_3O_(12) K'=11.32 tan δ = 0.0006 Nd_(2.95)Mg_(1.48)ln_(.68)Ga_(1.54)Ge_(1.32)O_(12) K'=11.86 tan δ = 0.0009 NaCa_2Mg_2V3O_(12) K'=10.32 tan δ = 0.0007 YVO_4 K_a'=9.68 tan δ_a = 0.0010 K_c' = 16.59 tan δ_c = 0.0278. The dielectric polarizabilities of Fe_2O_3, GeO_2, and V_2O_5 derived from the dielectric constants of the above compounds are 10.5, 5.5, and 15.8 Å^3, respectively. The agreement between measured dielectric polarizabilities as determined from the Clausius-Mosotti equation and those calculated from the sum of oxide polarizabilities according to α_D(mineral) = Σα_D(oxides) for the above garnets is ~0.5%