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Do the A4c60 Fullerides Have a Broken-Symmetry Ground State?

Steven C. Erwin·Christoph Bruder
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Abstract

Band theory predicts both K3C60 and K4C60 to be metals; various experimental probes show that while K3C60 is indeed metallic, K4C60 appears to be insulating. The standard view of this apparent failure of the single-particle picture is that electron correlation is predominant. We describe an alternative scenario, motivated on theoretical grounds, which invokes a spin- or charge-density-wave state to explain the observed insulating behavior.

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Steven C. Erwin, Christoph Bruder. 1993-09-20. Do the A4c60 Fullerides Have a Broken-Symmetry Ground State?. https://doi.org/10.1016/0921-4526(94)91917-8

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