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Random-Site Cation Ordering and Dielectric Properties of PbMg1/3Nb2/3o3-PbSc1/2Nb1/2o3

I. P. Raevski·S. A. Prosandeev·S. M. Emelyanov·F. I. Savenko·I. N. Zakharchenko·O. A. Bunina·A. S. Bogatin·S. I. Raevskaya·E. S. Gagarina·E. V. Sahkar·L. Jastrabik
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Abstract

(1-x)PbMg1/3Nb2/3O3-(x)PbSc1/2Nb1/2O3 (PMN-PSN) solid solution crystals have been grown by the flux method in the whole concentration range. X-ray supercell reflections due to B-cation ordering were observed for as-grown crystals from the 0.1 < x < 0.65 compositional range. Though the ordered domains are rather large (~50 nm) the relaxor-like dielectric behavior is observed for compositions with x < 0.6. The diffusion of the dielectric permittivity maximum in as-grown crystals is the lowest at x = 0.6 and increases towards the end members of solid solution. Such behavior is explained within a Bragg-Williams approach by employing the random layer model. At x ~ 0.6 the excitation energy determined from the Vogel-Fulcher relation exhibits a jump which we regard to changing the kind of the polar regions from PbMg1/3Nb2/3O3 to PbSc1/2Nb1/2O3 related type.

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I. P. Raevski, S. A. Prosandeev, S. M. Emelyanov, F. I. Savenko, I. N. Zakharchenko, O. A. Bunina, A. S. Bogatin, S. I. Raevskaya, E. S. Gagarina, E. V. Sahkar, L. Jastrabik. 2003-02-25. Random-Site Cation Ordering and Dielectric Properties of PbMg1/3Nb2/3o3-PbSc1/2Nb1/2o3. https://arxiv.org/abs/cond-mat/0302520

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