Study of superstructure Ⅱ in multiferroic BiMnO3

• 来源期刊: 中国物理B（英文版）
• 关键词: multifcrroics BiMnO3 high-resolution transmission electron microscopy image processing
• 年，卷（期）: 2008,（9）
• 页码范围: 3163-3169
• 页数: 7页
• 语种: 英文

摘要

The crystal structure of the minor phase,named superstructure Ⅱ,existing in multiferroic compound BiMnO3 has been studied by electron diffraction and high-resolution transmission electron microscopy.Domains of major and minor phases coexisting in BiMnO3 were observed in high-resolution electron microscope images.The unit cell of minor phase Was determined to be triclinic with the size 4×4×4 times as large as the distorted perovskitc subcell.The[111] and [101]projected structure maps of the minor phase have been derived from the corresponding images by means of the image processing.A possible rough three-dimensional(3D)structure model was proposed based on the 3D structural information extracted from the two projected structure maps.Since there is no inversion centre in the proposed model,the minor phase may contribute to the ferroelectric property of BiMnO3.