Do the A4C60 fullerides have a broken-symmetry ground state?
نویسنده
چکیده
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 spinor charge-density-wave state to explain the observed insulating behavior. (To appear in Physica B)
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