Excitation transfer photoelectron spectroscopy

D. M. Cyr, G. A. Bishea, M. G. Scranton, M. A. Johnson, J. Chem. Phys. 97, 5911 (1992). Observation of Charge-Transfer Excited States in the I CH3I, I CH3Br, and I -CH2Br2 SN2 Reaction Intermediates Using Photofragmentation and Photoelectron Spectroscopies. 

The main peaks in X-ray Photoelectron Spectroscopy (XPS) for molecules appear because of the photoionization of core electrons. In addition, satellite peaks on the high binding energy side of the main peak have often been observed. These peaks are generally referred to as shakeup satellite peaks. In the sudden approximation, the shakeup process which accompanies photoionization can be considered as a two-step process. First, a core electron is emitted as a photoelectron, creating an inner shell vacancy. In the next step, electron(s) in the same molecule transfer from valence orbital(s) to unoccupied orbital(s) with relaxation of orbital energies. It is important to study these satellites in order to understand the valence and excited states of molecules (1). 

The UV and luminescence spectra of benzo[Z>]selenophene-doped naphthalene show that the properties of localized excitation states are different <83Ml 213-03). Charge transfer complexes of selenophene and some condensed derivatives were examined by UV, IR, and photoelectron spectroscopy and the experimental ionization potentials are in agreement with the calculated ones <82CS214>. 

In photoelectron spectroscopy a photon incident on a surface is absorbed and its energy is transferred to an electron, which is excited from a bound state into the continuum. The energy distribution of these photoemitted electrons is measured. 

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