title: N-K near-edge x-ray-absorption fine structures of acetonitrile in gas phase.
abstract: The dynamic processes of N(1s) core-hole excitation in gas-phase CH3CN molecule have been studied at both Hartree-Fock and hybrid density-functional theory levels. The vibrational structure is analyzed for fully optimized core-excited states. Frank-Condon factors are obtained using the linear coupling model for various potential surfaces. It is found that the vibrational profile of the N-K absorption can be largely described by a summation of two vibrational progressions: a structure-rich profile of nu(CN) stretching mode and a large envelope of congestioned vibrational levels related to the strong (-C-CN) terminal bending bond. Excellent agreement between theoretical and experimental spectra is obtained.
authors.affiliation: Laboratoire de Chimie Physique, Matière et Rayonnement, Unité Mixte de Recherche (UMR) 7614, Université Pierre et Marie Curie, Paris, Cedex 05, France. carniato@ccr.jussieu.fr
authors.forename: Stéphane
authors.initials: S
authors.lastname: Carniato
authors.forename: Richard
authors.initials: R
authors.lastname: Taïeb
authors.forename: Edwin
authors.initials: E
authors.lastname: Kukk
authors.forename: Yi
authors.initials: Y
authors.lastname: Luo
authors.forename: Barbara
authors.initials: B
authors.lastname: Brena