Electron donor--electron acceptor interactions in surface metal--metal bonds: The Cu/Re(0001) and Pd/Re(0001) systems

Journal Article · Wed Jul 01 00:00:00 EDT 1992 · Journal of Vacuum Science and Technology, A (Vacuum, Surfaces and Films); (United States)

DOI:https://doi.org/10.1116/1.578095· OSTI ID:7201003

Rodriguez, J A; Campbell, R A; Goodman, D W ^[1]

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1. Department of Chemistry, Texas A M University, College Station, Texas 77843 (United States)

The interaction of Cu and Pd with Re(0001) has been examined by means of temperature programmed desorption and x-ray photoelectron spectroscopy. A Cu monolayer desorbs from Re(0001) at a temperature of 1180 K and has an electron density similar to that of the surface atoms of Cu(100). Pd adatoms on Re(0001) are electronically perturbed with respect to surface atoms of Pd(100), desorbing at a temperature of 1450 K. By comparison of these results with those previously presented in the literature for Pd and Cu adlayers, we found that there is a correlation between the electronic perturbations in the adlayers, the strength of the admetal--substrate bonds, and the ability of the adatoms to chemisorb CO. The results indicate that formation of a surface metal--metal bond leads to a gain in electrons by the element initially having the larger fraction of empty states in its valence band. This behavior is contrary to that observed in bulk alloys, indicating that the electronegativities of the surface atoms are substantially different from those of the bulk. A method to establish a scale of surface electronegativities is proposed.

• OSTI ID: 7201003
• Journal Information: Journal of Vacuum Science and Technology, A (Vacuum, Surfaces and Films); (United States), Vol. 10:4; ISSN 0734-2101
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
COPPER
ELECTRONEGATIVITY
PALLADIUM
RHENIUM
SORPTIVE PROPERTIES
CHEMICAL BONDS
DESORPTION
ELECTRON DENSITY
PHOTOELECTRON SPECTROSCOPY
X RADIATION
ELECTROMAGNETIC RADIATION
ELECTRON SPECTROSCOPY
ELEMENTS
IONIZING RADIATIONS
METALS
PLATINUM METALS
RADIATIONS
SORPTION
SPECTROSCOPY
SURFACE PROPERTIES
TRANSITION ELEMENTS
400201* - Chemical & Physicochemical Properties