Electronic structure of Sn/Cu(100)-(2?2 × 2?2)R45°

We present measurements of the Fermi surface and underlying band structure of Sn/Cu(100)-(2?2 × 2?2)R45° . This phase is observed for a coverage of 0.60-0.65 monolayers. Its electronic structure is characterized by a free-electron-like surface band folded with the reconstruction periodicity. At variance with other surface phases of Sn on Cu(100), no temperature-induced phase transition is observed for this phase from 100 K up to the desorption of Sn.