Vibrationally resolved partial cross sections and asymmetry parameters for carbon K-shell photoionization of the CO₂molecule

Abstract

We have measured the vibrationally resolved partial cross sections σ v 1 and asymmetry parameters β v 1 for C K-shell photoionization of the CO 2 molecule in the u shape resonance region above the C K-shell ionization threshold. The positions of both the maxima of σ v 1 and the minima of β v 1 move towards the C K-shell threshold with increasing symmetric stretching vibrational excitation v 1 in the C 1s single-hole state. Calculations employing the relaxed-core Hartree-Fock approach reproduce the observed vibrational effects.

Role of the recoil effect in two-center interference in X-ray photoionization

“…It is interesting to note that the effective displacement given by Eq. (24) is the same as the one that was obtained earlier in the theory of shape resonances [26][27][28], as a natural consequence of the Taylor expansion.…”

Changes in site-specific shape resonances in nitrogen K-shell photoionization of N2O induced by vibrational excitation

“…High-resolution measurements for core-level photoelectron spectra (PES) of molecules carried out on soft x-ray beamlines at the third generation synchrotron radiation light sources revealed the distribution of the vibrational levels in the core-hole state and the photoelectron angular distribution vary in the shape resonance region. Such studies have been predicted by Dehmer et al [2] and reported for CO [3], H 2 CO [4], N 2 [5], C 2 H 2 [6], CO 2 [7,8] and NO [9].…”

“…"#$%!& seem to be similar for N c while they are significantly different for N t . Below we will extract this difference employing the spectral line fitting procedure described elsewhere [4][5][6][7][8][9][10].…”

“…Briefly, for both N c and N t , PESs of the vibrationally-ground level, ! "#$%& , were fitted using the PCI-distorted line profiles convoluted with the Gaussian profile as described in details elsewhere [4][5][6][7][8][9][10]. !…”

Identifying and Understanding Strong Vibronic Interaction Effects Observed in the Asymmetry of Chiral Molecule Photoelectron Angular Distributions

“…The influence of full Herzberg-Teller type vibronic interaction has been discussed [6] in this context, but more typically approaches based upon treating the parametric dependence of the electronic matrix element upon nuclear geometry have provided understanding. Such investigations have mainly addressed the localized K-edge ionization of diatomic [7][8][9][10][11] and triatomic [12,13] molecules in the vicinity of shape resonances. Only very recently have such case studies extended to consider PADs in larger non-linear polyatomics [14] and/or valence shell ionization.…”