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arXiv · 1003.3294

Prominent 5d-orbital contribution to the conduction electrons in gold

A. Sekiyama·J. Yamaguchi·A. Higashiya·M. Obara·H. Sugiyama·M. Y. Kimura·S. Suga·S. Imada·I. A. Nekrasov·M. Yabashi·K. Tamasaku·T. Ishikawa
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Abstract

We have examined the valence-band electronic structures of gold and silver in the same column in the periodic table with nominally filled d orbitals by means of a recently developed polarization-dependent hard x-ray photoemission. Contrary to a common expectation, it is found that the 5d-orbital electrons contribute prominently to the conduction electrons in gold while the conduction electrons in silver are to some extent free-electron-like with negligible 4d contribution, which could be related to a well-known fact that gold is more stable than silver in air. The 4d electron correlation effects are found to be essential for the conduction electron character in silver.

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A. Sekiyama, J. Yamaguchi, A. Higashiya, M. Obara, H. Sugiyama, M. Y. Kimura, S. Suga, S. Imada, I. A. Nekrasov, M. Yabashi, K. Tamasaku, T. Ishikawa. 2010-03-17. Prominent 5d-orbital contribution to the conduction electrons in gold. https://doi.org/10.1088/1367-2630%2F12%2F4%2F043045

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