NMR study of the electronic properties and stability of quasicrystals

Using NMR, the electronic properties of the stable quasicrystalline phases Al sub 57 Cu sub 10.8 Li sub 32.2 and Al sub 62 Cu sub 25.5 Fe sub 12.5 and of two crystalline approximants, the bcc R phase Al sub 56 Cu sub 12 Li sub 32 and the rhombohedral Al sub 62.8 Cu sub 26 Fe sub 11.2 phase have been studied. Low values of the density of states the Fermi level are observed in the crystalline and in the quasicrystalline phases. The existence of a pseudogap at the Fermi level is therefore not a consequence of the quasi-periodicity. These results renew the debate on the stability of quasicrystals.