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Symmetry breaking and restoring under high pressure: the amazing behaviour of the "simple" alkali metals

G. G. N. Angilella·F. Siringo·R. Pucci
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Abstract

We argue that an ionic lattice surrounded by a Fermi liquid changes phase several times under pressure, oscillating between the symmetric phase and a low-symmetry dimerized structure, as a consequence of Friedel oscillations in the pair potential. Phase oscillations explain the tendency towards dimerization which has been recently reported for the light alkali metals under high pressure. Moreover, a restoring of the symmetric phase is predicted for such elements at an even higher density.

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G. G. N. Angilella, F. Siringo, R. Pucci. 2003-03-03. Symmetry breaking and restoring under high pressure: the amazing behaviour of the "simple" alkali metals. https://doi.org/10.1140/epjb%2Fe2003-00105-8

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