Please use this identifier to cite or link to this item:
|Title:||Valence one-electron and shake-up lonisation bands of polycyclic aromatic hydrocarbons. IV The dibenzanthracene species.||Authors:||DELEUZE, Michael||Issue Date:||2006||Publisher:||Elsevier||Source:||CHEMICAL PHYSICS, 329(1-3). p. 22-38||Abstract:||A comprehensive study of the He (I) ultra-violet photoelectron spectra of the 1.2,3.4; 1.2,5.6 and 1.2,7.8 isomers of dibenzanthracene up to the double ionisation threshold at not, vert, similar18 eV is presented with the aid of one-particle Green’s Function calculations performed using the outer-valence Green’s Function (OVGF) approach and the third-order algebraic diagrammatic construction [ADC(3)] scheme, along with basis sets of improving quality. Suited extrapolations of the ADC(3) results for the one-electron energies characterising the π-band system (εb < 10 eV) to Dunning’s correlation consistent basis set of triple zeta quality (cc-pVTZ) enable theoretical insights into HeI measurements which approach chemical accuracy (1 kcal/mol or 43.4 meV). In contrast, a confrontation of simulated spectral envelopes with high-resolution He I photoelectron spectra indicates that polycyclic aromatic molecules with sterically overcrowded bay regions are more susceptible to undergo vibronic coupling complications at the σ-ionisation onset. OVGF/cc-pVDZ or OVGF/cc-pVTZ pole strengths smaller than 0.85 systematically corroborate a breakdown of the orbital (or one-electron) picture of ionisation at the ADC(3)/6-31G levels. The extent of shake-up bands is correspondingly related to topological, structural and magnetic criteria of aromaticity. Comparison is made with calculations of the lowest doublet–doublet excitation energies of the related radical cations, by means of time-dependent density functional theory (TDDFT).||Keywords:||Aromaticity; Chemical accuracy; Electronic relaxation; Electronic correlation; Excited states; Photoelectron spectra; Propagator; Vibronic couplings||Document URI:||http://hdl.handle.net/1942/1451||ISSN:||0301-0104||e-ISSN:||1873-4421||DOI:||10.1016/j.chemphys.2006.06.037||ISI #:||000241574500005||Category:||A1||Type:||Journal Contribution||Validations:||ecoom 2007|
|Appears in Collections:||Research publications|
Show full item record
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.