Cation distribution in spinel iron oxides by resonant X-ray scattering

2017 Fiscal Year Final Research Report

• Project/Area Number: 15H03747
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Petrology/Mineralogy/Economic geology
• Research Institution: Tohoku University (2016-2017); Tokyo Institute of Technology (2015)
• Principal Investigator: Okube Maki 東北大学, 金属材料研究所, 准教授 (10397060)
• Co-Investigator(Renkei-kenkyūsha): Sasaki Satoshi 東京工業大学, 科学技術創成研究院, 名誉教授 (10162364)
• Project Period (FY): 2015-04-01 – 2018-03-31
• Keywords: X線異常分散効果 / 共鳴散乱 / スピネル構造 / 陽イオン分布

Outline of Final Research Achievements

Understanding of cation distribution in spinel-type oxides is essential since their magnetic properties highly depend on the cation distribution. The site occupancies of cations in spinel oxides were analyzed using X-rays with energies near absorption edges. The resonant scattering experiments allowed us to distinguish cations that have close number of electrons or the same cations with different valence. Spinel structure has two different crystallographyc sites; tetrahedral site and Octahedral sites. The site occupancies of Mn and Fe for MnxFe3-xO4, Fe2+, Fe3+ and Ti4+ for TixFe3-xO4 was distinctively analyzed. X-ray resonant magnetic scattering experiments with circularly polarized X-ray were also carried out to develop site-selective magnetic moment analysis and theoretical expression for asymmetric ratio was discussed.

Free Research Field

X線結晶学