Core electron-binding energies modeling

The ionization potentials can be analyzed by a point charge model to estimate the charge distribution. This analysis is based on the elementary idea that the core-electron binding energy of an atom in trifluoromethylbenzene relative to the core-binding energy of a related atom in an appropriate reference com-... 

M. Boman, H, Agren, and S. Stafstrom, A J-SCF study of core electron binding energies of model molecules for the aluminum/polythiophene interface, J. Phys. Chem 99 16597 (1995). 

Figure 2 displays a qualitative correlation between the increase or decrease in CO desorption temperature and relative shifts in surface core-level binding energies (Pd(3d5/2), Ni(2p3/2), or Cu(2p3/2) all measured before adsorbing CO) [66]. In general, a reduction in BE of a core level is accompanied by an enhancement in the strength of the bond between CO and the supported metal monolayer. Likewise, an opposite relationship is observed for an increase in core-level BE. The correlation observed in Figure 2 can be explained in terms of a model based on initial-state effects . The chemisorption bond on metal is dominated by the electron density of the occupied metal orbital to the lowest unoccupied 27t -orbital of CO. A shift towards lower BE decreases the separation of E2 t-Evb thus the back donation increases and vice versa. 

Electron spectroscopy, particularly photoemission, has been used successfully to study the electronic structure of small metal clusters deposited on well-characterized model systems [3-5,8,16,20,34-42,66,71,72,76-86]. The core-level binding energy... 

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