Insights on the site-selective fragmentation of CF2Cl2 and CH2Cl2 at the chlorine K-edge from ab initio calculations

Disentangling the resonant Auger spectra of ozone: overlapping core-hole states and core-excited state dynamics

“…We adopted the cc-pVTZ basis set 75 in all calculations. Multi-reference calculations of core-excited and core-ionized states 28,76,77 relevant to, respectively, resonant and non-resonant Auger spectra were carried out by placing the relevant core orbitals in the RAS1 space and enforcing single electron occupation in RAS1 by means of the HEXS projection technique 78 available in OpenMolcas, 60 which corresponds to applying the core-valence separation technique. 79 RAS2 was used for complete electron distribution, i.e.…”

Soft X-ray Spectroscopy Simulations with Multiconfigurational Wave Function Theory: Spectrum Completeness, Sub-eV Accuracy, and Quantitative Reproduction of Line Shapes

“…Nonetheless, the coupling of the electronic states with nuclear degrees of freedom can also affect the line shape, in terms of additional (asymmetric) broadening and/or appearance of vibronic fine structure. So far, the vibronic effects have been addressed by means of approaches based on potential energy surfaces (PES) mapping, typically complemented by time-dependent wave packet propagation, on small molecular systems and/or along a very restricted number of modes. ,,− This allows an accurate description of the vibrational structure (especially when sensitive techniques such as resonant inelastic X-ray scattering are simulated) and of possible dissociative coordinates but cannot be extended to systems of medium/large size. Evaluation of Franck–Condon overlaps within the harmonic approximation of the PES topology, also known as the DHO (or linear vibronic coupling) model, has been also proposed as a viable approximation − but not coupled to RASSCF/RASPT2 quantum chemistry data in this context, to the best of our knowledge.…”