title: Charge transfer in the Cl-CO cluster induced by core ionization.
abstract: Ab initio calculations of core-ionization spectra of the anion-molecule Cl-CO cluster are performed. Particular attention is paid to the investigation of charge-transfer screening processes accompanying core ionization of the CO molecule in the cluster. The charge-transfer processes are very efficient and favored by the presence of a low-lying unoccupied pi* orbital in CO capable of accepting an electron from Cl-. The O1s(-1) and C1s(-1) core-ionization spectra are calculated and compared. Both reveal a breakdown of the quasiparticle picture of core ionization caused by the charge-transfer processes. Remarkable differences between these two spectra are found which manifest themselves in distinct intensity distributions in the prominent low-energy spectral bands. The underlying reason for these differences is elucidated and linked with the preference of the pi* orbital to localize mainly on carbon. Core-ionization spectra of anion-molecule clusters are very sensitive to the type of the molecule involved as the comparative analysis of the O1s(-1) core-ionization spectra of the Cl-CO and Cl-H(2)O clusters show.
authors.affiliation: Theoretical Chemistry, Institute of Physical Chemistry at Heidelberg University, Im Neuenheimer Feld 229, 69120 Heidelberg, Germany. nikolai.kryzhevoi@pci.uni-heidelberg.de
authors.forename: Nikolai V
authors.initials: NV
authors.lastname: Kryzhevoi
authors.forename: Nickolay V
authors.initials: NV
authors.lastname: Dobrodey
authors.forename: Lorenz S
authors.initials: LS
authors.lastname: Cederbaum