Abstract Magnetic dilution and NEXAFS spectroscopy were used in the study of iron-containing solid solutions Bi2MNb2O9 (M – Ba, Sr) with layered perovskite-like structure. The analysis of the NEXAFS Fe2p-spectra of iron-containing solid solutions and iron oxides revealed that the studied Fe atoms were mainly in the +3 oxidation state. The study of magnetic susceptibility of the Bi2Ba(Sr)Nb2−2xFe2xO9−δ solid solutions showed the influence of atoms of the second coordination sphere on the distribution, degree of clustering, and intensity of exchange interactions in clusters of iron atoms. It was established that iron (III) atoms exhibited selectivity in filling the cation positions, preferring less distorted octahedral positions. The substitution of barium with strontium atoms led to intensification of the exchange of the ferromagnetic type and to a decrease in the degree of clustering of iron atoms in the solid solutions Bi2SrNb2−2xFe2xO9−δ.

中文翻译：

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钡和锶原子对含铁固溶体Bi2MNb2O9(M-Ba,Sr)磁性能的影响

摘要 磁性稀释和 NEXAFS 光谱用于研究具有层状钙钛矿状结构的含铁固溶体 Bi2MNb2O9 (M – Ba, Sr)。对含铁固溶体和氧化铁的 NEXAFS Fe2p 光谱的分析表明，所研究的 Fe 原子主要处于 +3 氧化态。Bi2Ba(Sr)Nb2-2xFe2xO9-δ固溶体磁化率的研究表明，第二配位球的原子对铁原子团簇中的分布、团聚程度和交换相互作用强度的影响。已确定铁 (III) 原子在填充阳离子位置时表现出选择性，更喜欢扭曲较少的八面体位置。