ae9b00223_si_001.pdf (127.74 kB)
Download fileValence Electron and Chemical State Analysis of Be12M (M = Ti, V) Beryllides by Soft X‑ray Emission Spectroscopy
journal contribution
posted on 2019-03-07, 00:00 authored by Keisuke Mukai, Ryuta Kasada, Kiyohiro Yabuuchi, Satoshi Konishi, Jae-Hwan Kim, Masaru. NakamichiBe-rich
intermetallics (beryllides) have gathered wide attentions to be adopted
for high temperature environments, such as an advanced neutron multiplier
in fusion reactors. This study reveals the valence electron structure
of Be12M (M = Ti,V) by using soft X-ray emission spectroscopy
with ultrahigh resolution (∼0.22 eV). The Be–Kα
spectra from the Be12M phases show significantly lower
densities of the occupied states near the Be–K edge than thaose
of metallic beryllium. Theoretical calculations indicate that changes
in the valence electron structure are derived from the large downward
shift of the Fermi level in Be12M, by at least 0.8 eV.
Based on the knowledge of the valence electron structures and the
chemical shift, chemical state mappings of BeO and Be12V in the oxidized beryllide specimen were successfully obtained.
The approach is applicable for visualization and identification of
metallic/oxidized phase in light-element compounds by electron microscope.