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Dielectric properties of crystalline polyantimonic acid-phosphate composites

“…The changes observed for the 0.2KH 2 PO 4 /0.8CPAA composite approximately correspond to the degree of substitution of K + /H + 0.08 in CPAA. For composites with sodium (NaDP) and ammonium (ADP) phosphates, the changes are less significant, which is consistent with the data of [5,6] about the structural changes in CPAA during ion exchange in solutions containing Na + and ions. When the mass fraction of phosphate became higher than 0.2, the XRD patterns of the composites con tained additional maxima corresponding to the struc tures of pure phosphates.…”

“…As shown above, the ion exchange occurs during the synthesis of the compos ites, and the degree of ion exchange for different sys tems probably increases in the same series. The substi tution of the proton groups of CPAA by alkaline ions is known to decrease the conductivity and permeabil ity of CPAA [11]. Therefore, the observed tendency toward variation of the dielectric properties can serve as further proof of the determining role of the interface layer.…”

“…Its value is close to 4.1, which probably corresponds to high frequency (elec tron) permeability. As is known, the ion exchange of the proton groups of CPAA by the ammonium ions leads to a dramatic drop of conductivity due to the high affinity of ammonia molecules to protons, which are no longer involved in the transfer [11]. At high mass fraction of ammonium phosphate, the ion exchange probably leads to a decrease in the concen tration of mobile carriers and in the proton conductiv ity, so that the contribution of the latter to the dielec tric constant becomes small compared with the elec tron contribution at high frequencies.…”

Electric and ionic conductivity of potassium antimony tungstate with addition of alkali metals

“…Potassium antimony tungstate K 1-x Me x SbWO 6 (Me = Na, Li) with different compositions were obtained in the concentration range 0≤x≤0.6 and 0≤x≤0.4, respectively, by step ∆x = 0.1 according to the method described in [1][2][3][4][5][6][7][8][9]. The X-ray diffraction patterns of the samples of potassium antimonate tungstate of the pyrochlore type doped with sodium and lithium ions (K 1-x Na x SbWO 6 (0≤x≤0.6) and K 1-x Na x SbWO 6 (0≤x≤0.4)) contain a certain set of diffraction maxima, which is satisfactorily described for cubic crystals.…”

“…The X-ray diffraction patterns of the samples of potassium antimonate tungstate of the pyrochlore type doped with sodium and lithium ions (K 1-x Na x SbWO 6 (0≤x≤0.6) and K 1-x Na x SbWO 6 (0≤x≤0.4)) contain a certain set of diffraction maxima, which is satisfactorily described for cubic crystals. From the analysis of the laws of extinction of reflexes, it follows that in the specified concentration intervals the phases with a pyrochloretype structure with a spatial group of symmetry Fd3m are formed [1][2][3][4][5][6][7][8][9][10][11].…”