Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5396823 | Journal of Electron Spectroscopy and Related Phenomena | 2008 | 12 Pages |
Abstract
Single-component clusters of methyl chloride and methyl bromide have been produced by adiabatic expansion and their C 1s, Cl 2p and Br 3d photoelectron spectra recorded using synchrotron radiation and a high-resolution electron analyzer. The experimentally observed cluster-to-monomer shifts in core-level ionization energies are interpreted in terms of theoretical models based on molecular dynamics (MD) in conjunction with polarizable force fields developed and validated in the course of this work. MD simulations have also been used to explore the global and local structure of the clusters, providing evidence for a predominance of anti-parallel, head-to-tail arrangement of neighboring molecules. Whereas the cluster-to-monomer shifts are strongly dominated by polarization effects, the polarization contribution is very similar for ionization of carbon and the halogen, respectively. The difference in cluster shifts between the two ionization sites within the same molecule, C vs. Cl or C vs. Br, is thus determined by permanent electrostatic moments, i.e. the magnitude and direction of the permanent dipole moment and the local alignment of dipoles.
Keywords
Related Topics
Physical Sciences and Engineering
Chemistry
Physical and Theoretical Chemistry
Authors
J. Harnes, M. Abu-samha, M. Winkler, H. Bergersen, L.J. Sæthre, K.J. Børve,