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利用北京同步辐射光源，对居里点在室温附近的掺铁钽铌酸钾光折变晶体进行了Ｘ射线白光形貌术研究．观察显示，晶体内部除了杂质偏析物和一组沿［０１０］方向的生长层外，还有一组与之正交的畴组态，后者被发现不满足一般面缺陷的衬度消光规律，仅有异常散射效应揭示其衬度．利用同步辐射波长的可调谐性，揭示了该组畴随波长改变其衍时衬度变化的规律，而且畴的衍射强度被发现违背Ｆｒｉｅｄｅｌ定律．依据实验证据，这组畴被确认为１８０°铁电畴．对畴形成原因和晶体生长特性进行了讨论．
The X-ray white morphology of the iron-doped tantalum potassium niobate photorefractive crystal near the Curie point near room temperature was studied by using Beijing synchrotron radiation light source. The observation shows that in addition to the impurity segregation and a group of growth layers along the [010] direction, there are a set of orthogonal configuration in the crystal. The latter is not found to meet the law of contrast extinction of general surface defects, only Abnormal scattering effect reveals its contrast. The tunability of the wavelength of synchrotron radiation is used to reveal the regularity of the change of the group ’s time dependency with wavelength, and the diffraction intensity of the domain is found to violate the Friedel’ s law. Based on experimental evidence, the domains were identified as 180 ° ferroelectric domains. The reasons for the formation of the domains and the crystal growth characteristics are discussed.