Work

Atomic structure of selenium incorporated into mackinawite unveiled by density functional theory

Year: 2026

Type: article

Abstract: Selenium-79 is an important contributor to the long-term radiological hazards in deep geological repositories for high‑level radioactive waste. Investigating the environmental behavior of selenium (Se) is crucial for its safety assessment. In this study, the stable structures of Se incorporated in mackinawite, an iron sulfide mineral, were elucidated using density functional theory (DFT) calculations. The results indicate that it is important for Se atoms to be separated by a sufficient distance from one another. Furthermore, over the full concentration range, a symmetric structure at a Se atomic fraction of 0.5 was found to be the most stable.

Source: Journal of Nuclear Science and Technology

DOI: 10.1080/00223131.2026.2747906

Authors: Akiko Yamaguchi, Kevin M. Rosso, Paul Clarence M. Francisco, Masahiko Okumura

Institutions: Japan Atomic Energy Agency, Pacific Northwest National Laboratory

Language: English

Topic: Nuclear materials and radiation effects

Subfield: Materials Chemistry

Field: Materials Science

Domain: Physical Sciences

Open Access status: hybrid

Funders: Ministry of Economy, Trade and Industry, Agency for Natural Resources and Energy, Japan Atomic Energy Agency

Awards: G1205615916, G3308795840, G3978147871, G6856085930, G7206073476