Authors: R E Whitfield A J Studer D J Goossens
Publish Date: 2011/08/12
Volume: 43, Issue: 5, Pages: 1429-1433
Abstract
Structural disorder seems to relate to the useful physical properties of ferroelectrics and relaxors One such material is PZN hboxPbZn 1/3hboxNb 2/3hboxO 3 To explore what aspects of the disorder are specific to the polarized state the temperature dependence of diffuse scattering in PZN has been investigated The data were collected using both neutron and Xray single crystal experiments in a range of temperatures from 50 K to 500 K −223 °C to 227 °C It has been found that some features like the diffuse scattering from the Bsite ordering remain unchanged with change of temperature in terms of both intensity and peak shape However other diffuse scattering features evolve with T for example the size effect scattering around the Bragg peaks The sizeeffect becomes less pronounced with increasing temperature with the diffuse scattering becoming more symmetric around the Bragg peaks The diffuse rods caused by the planar domains change only slightly with temperature This finding indicates that the planar domains persist into the paraelectric state but that the correlation between lead displacement and the average separation of adjacent lead atoms becomes weaker suggesting that this size effect may be crucial to the ferroelectric propertiesWe acknowledge the Australian Research Council for support through its Discovery Projects program and the Australian Institute for Nuclear Science and Engineering for their financial support Dr JS Forrester kindly supplied the PZN crystal DJG thanks Dr AP Heerdegen and Prof TR Welberry of the Research School of Chemistry at the Australian National University for their advice and assistance
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