Structural characterization of Eu-HONTA complexes by IBIL and EXAFS analyses

• Published in: Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms Vol. 477; no. C; pp. 60 - 65
• Main Authors: Watanabe, Sou, Sano, Yuichi, Okada, Makoto, Matsuura, Haruaki, Hagura, Naoto, Kada, Wataru
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 15.08.2020; Elsevier
• Subjects: Adsorbent; Complex; EXAFS; HONTA; IBIL; Adsorbent; IBIL; EXAFS; HONTA; Complex
• ISSN: 0168-583X; 1872-9584
• DOI: 10.1016/j.nimb.2019.10.004

IBIL and EXAFS analyses were carried out on Eu-HONTA complexes formed in solvent extraction and adsorbent systems. EXAFS analysis suggested that there was not significant difference in the structure observed in the two systems. Characteristic peaks in IBIL spectra were attributed to transition of 4f electrons in Eu3+ ion in complexes with HONTA, and distinct difference was found in the profile of 5D0 → 7F4 transition. Since the number of the nearest neighboring O atoms around Eu and the nearest Eu-O distance must be the same for all conditions, the difference in the IBIL profile was considered to be caused by different symmetry of HONTA or NO3− around a Eu3+ ion. Combination of those two techniques was shown to be an effective method to investigate complexes with organic compounds, and further analysis on the IBIL spectra is expected to reveal precise structure of complexes formed in the adsorbent and the solvent systems.