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arXiv · 1104.3486

Plasmons in Sodium under Pressure: Increasing Departure from Nearly-Free-Electron Behavior

I. Loa·K. Syassen·G. Monaco·G. Vanko·M. Krisch·M. Hanfland
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Abstract

We have measured plasmon energies in Na under high pressure up to 43 GPa using inelastic x-ray scattering (IXS). The momentum-resolved results show clear deviations, growing with increasing pressure, from the predictions for a nearly-free electron metal. Plasmon energy calculations based on first-principles electronic band structures and a quasi-classical plasmon model allow us to identify a pressure-induced increase in the electron-ion interaction and associated changes in the electronic band structure as the origin of these deviations, rather than effects of exchange and correlation. Additional IXS results obtained for K and Rb are addressed briefly.

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I. Loa, K. Syassen, G. Monaco, G. Vanko, M. Krisch, M. Hanfland. 2011-04-18. Plasmons in Sodium under Pressure: Increasing Departure from Nearly-Free-Electron Behavior. https://doi.org/10.1103/physrevlett.107.086402

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