Atomic wires on furrowed transition metal surfaces.
At low coverages, alkali, alkaline earth, and rare earth layers adsorbed on furrowed transition metal surfaces--such as the Mo(112) surface--demonstrate a quite unusual behavior. In contrast to well-known formation of one-dimensional wires lying in furrows of reconstructed surfaces of semiconductors and noble metals, these metals on the W(112), Mo(112), and Re(1010) surfaces tend to form commensurate linear structures built of monoatomic chains directed across the furrows. Monte-Carlo simulations of the increasing disorder of the chains with increasing temperature provides a transparent presentation of typical fluctuations in such linear structures. Such studies provide insight into the parameters of indirect interaction that are the basis for the formation of the atomic wires. Increasing coverage leads to a one-dimensional compression of the layers along the furrows, which results in dramatic changes in the surface electronic structure as revealed by photoemission ultraviolet photoelectron spectroscopy and electron energy loss (EELS) spectroscopies. Recent low energy electron diffraction, UPS, and electron energy loss spectroscopy data suggest a nonmetal to metal transition in the adsorbed alkaline earth layers when the coverage exceeds 1/2 monolayer and the film structure becomes incoherent with the substrate in direction along the furrows. The NMT in adsorbed layers is discussed in the framework of recent calculations of evolution of the band structure followed from increasing density of the films.
Yakovkin
I N
IN
Institute of Physics, National Academy of Sciences of Ukraine, Prospect Nauki 46, Kiev 03028, Ukraine.
D000327:Adsorption; D003460:Crystallization / Q000379:methods*; D003461:Crystallography / Q000379:methods; D004559:Electric Wiring; D004735:Energy Transfer; D008274:Magnesium / Q000737:chemistry; D008670:Metals / Q000138:chemical synthesis / Q000737:chemistry* / Q000145:classification / Q000302:isolation & purification; D008968:Molecular Conformation; D008982:Molybdenum / Q000737:chemistry; D010777:Photochemistry / Q000379:methods; D012666:Semiconductors; D013499:Surface Properties; D013696:Temperature; D028561:Transition Elements / Q000138:chemical synthesis / Q000737:chemistry* / Q000145:classification / Q000302:isolation & purification
D008670:Metals; D028561:Transition Elements; D008982:Molybdenum; D008274:Magnesium