DIELECTRIC LOSS OF BETA ALUMINA AND OF ION-EXCHANGED BETA ALUMINA

Dielectric loss measurements of a mixture consisting of a number of small single crystals of beta alumina suspended in alpha alumina have been made. The loss follows the Fuoss-Kirkwood empirical formula ε″= ε″max [ln (fmax/f)α]. Some speculations are made as to the cause of the width of the loss peaks. Substitution of other (K, Ag, Rb, NH4, Li, Tl) ions for sodium causes the loss curves to shift in a direction indicating higher resistivity of the substituted beta aluminas. A quantitative relation between the shift of the loss peaks and the known resistivity of the substituted beta aluminas as would be expected from the Maxwell-Wagner relations was unable to be made. © 1969 The American Institute of Physics.