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arXiv · 2106.00921

Anomalous diamagnetism of electride electrons in transition metal silicides

M. Hiraishi·K. M. Kojima·H. Okabe·A. Koda·R. Kadono·J. Wu·Y. Lu·H. Hosono
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Abstract

Intermetallic silicide compounds, LaScSi and Y$_5$Si$_3$, known for being hydrogen (H) storage materials, are drawing attention as candidates for electrides in which anions are substituted by unbound electrons. It is inferred from a muon spin rotation experiment that the local field at the muon site (which is the same site as that for H) in these compounds exhibits a large negative shift under an external magnetic field, which is mostly independent of temperature. Such anomalous diamagnetism signals a unique property of electride electrons associated with transition metals. Moreover, the diamagnetic shift decreases with increasing H content, suggesting that the electride electrons existing coherently in the hollow interstitial positions are adsorbed by H to form hydride ions (H$^-$)

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M. Hiraishi, K. M. Kojima, H. Okabe, A. Koda, R. Kadono, J. Wu, Y. Lu, H. Hosono. 2021-06-02. Anomalous diamagnetism of electride electrons in transition metal silicides. https://doi.org/10.1103/physrevb.103.l241101

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