Abstract—Perfect single crystals of BiFeO₃ have been grown by the solution-melt method. Chemical analysis has confirmed their cationic and anionic stoichiometry. Precision X-ray diffraction analysis has provided more accurate structural data for BiFeO₃ before and after γ-irradiation with a dose of 1.0 × 10⁶ rad. It has been established that the indicated structural characteristics of the BiFeO₃ crystal are in satisfactory agreement with the available literature data, although in our case a significant increase in their accuracy is observed (the R values (F > 2σ(F)) range from 0.017 to 0.023). For the first time, difference maps of the residual electron density have been constructed and possible positions of lone pairs of electrons for Bi³⁺ cations have been determined, which is important for establishing the structural conditionality of the ferroelectric properties in BiFeO₃. The effect of lone electron pairs on the specific features of the structural framework has been studied. The characteristic features of cationic polyhedra in the structure have been analyzed, including the calculation of their distortions and the valence state of cations. It has been shown that the structure of BiFeO₃ is resistant to irradiation with a given dose.

摘要—通过溶液-熔融法生长出完美的BiFeO ₃单晶。化学分析证实了它们的阳离子和阴离子化学计量。精密X射线衍射分析为1.0×10 ⁶ rad剂量的γ-辐照前后BiFeO _{3提供了更准确的结构数据。}已经确定 BiFeO ₃晶体的指示结构特征与现有文献数据令人满意地一致，尽管在我们的案例中观察到它们的准确性显着提高（R值（F > 2σ（F)) 范围从 0.017 到 0.023)。首次构建了剩余电子密度的差异图，并确定了Bi ³⁺阳离子孤对电子的可能位置，这对于确定BiFeO ₃中铁电性质的结构条件很重要。已经研究了孤电子对对结构框架的具体特征的影响。分析了结构中阳离子多面体的特征，包括其畸变的计算和阳离子的价态。已经表明，BiFeO ₃的结构可以抵抗给定剂量的辐照。