Electronic effects in the Mo(001) surface reconstruction: Two-dimensional Fermi surfaces and nonadiabaticity

The surface relaxation and band structure of Mo(112)

The experimental and theoretical surface band structures of Mo(112) are compared. This surface band structure mapping is presented with corrections included for the lattice relaxation of the Mo(112) surface. Quantitative low energy electron diffraction (LEED) has been used to determine the details of the Mo(112) surface structure. The first layer contraction is 14.9% by LEED intensity versus voltage analysis and is in general agreement with the 17.6% contraction found from total surface energy optimization. The electronic band structure is mapped out along [Formula: see text]-[Formula: see text] and [Formula: see text]-[Formula: see text] of the surface Brillouin zone (SBZ). There is strong evidence of electron-phonon coupling particularly in the region of the Fermi level band crossing at 0.54 Å(-1).

Fermi surface nesting and structural transition on a metal surface: In /Cu(001)

Peierls-type instability and structural phase transition are shown to occur on the surface of a normal metal. An In overlayer on Cu(001) undergoes a reversible transition at approximately 350 K. Scanning tunneling microscopy of the low-temperature, reduced-symmetry phase indicates a strong periodic lattice distortion (PLD). Angle-resolved photoemission of the high-temperature phase reveals that the In-derived surface resonance constitutes a square-shaped, quasi-two-dimensional Fermi surface within the projected bulk Cu bands. The Fermi surface exhibits one-dimensional nesting upon the transition, which is in agreement with the PLD periodicity.