Sedimentology and provenance of Carboniferous and Permian rocks of Athens County, Southeastern Ohio

Originally prepared for the 1998 North-Central Section meeting of the Geological Society of America

Image-potential states on clean and hydrogen-covered Pd surfaces: Analysis of a one-dimensional model

Theoretical calculations in a one-dimensional model give the energies of surface states on clean and hydrogen-covered Pd surfaces in very good agreement with those measured by high-resolution electron energy-loss spectroscopy and inverse photoemission experiments. Some general properties and the applicability of this class of one-dimensional models are discussed

Observation of new quantum interference effect in solids

In order to achieve quantum interference of free electrons inside a solid, we have modified the geometry of the solid so that de Broglie waves interfere destructively inside the solid. Quantum interference of de Broglie waves leads to a reduction in the density of possible quantum states of electrons inside the solid and increases the Fermi energy level. This effect was studied theoretically within the limit of the quantum theory of free electrons inside the metal. It has been shown that if a metal surface is modified with patterned indents, the Fermi energy level will increase and consequently the electron work function will decrease. This effect was studied experimentally in both Au and SiO2 thin films of special geometry and structure. Work function reductions of 0.5 eV in Au films and 0.2 eV in SiO2 films were observed. Comparative measurements of work function were made using the Kelvin Probe method based on compensation of internal contact potential difference. Electron emission from the same thin films was studied by two independent research groups using Photoelectron Emission Microscopy (PEEM).Comment: 11 pages, 5 figure

Unoccupied surface states on Pd(111) observed in very-low-energy electron diffraction and inverse photoemission: Theoretical interpretation

A three-dimensional calculation of projected electronic bulk and surface bands, spanning the energies studied by inverse photoemission and very-low-energy electron diffraction, reveals that the surface-electronic states observed by the two techniques are indeed two distinct states. We discuss their true character and the question of effective masses, and briefly comment on the validity of one-dimensional models

Limnogeology: Ancient and modern tales of an evolving Earth

Depto. de Mineralogía y PetrologíaFac. de Ciencias GeológicasTRUEpu