Observation of electron transfer mediated decay in aqueous solution

Photoionization is at the heart of X ray photoelectron spectroscopy XPS , which gives access to important information on a sample s local chemical environment. Local and non local electronic decay after photoionization in which the refilling of core holes results in electron emission from either the initially ionized species or a neighbour, respectively have been well studied. However, electron transfer mediated decay ETMD , which involves the refilling of a core hole by an electron from a neighbouring species, has not yet been observed in condensed phase. Here we report the experimental observation of ETMD in an aqueous LiCl solution by detecting characteristic secondary low energy electrons using liquid microjet soft XPS. Experimental results are interpreted using molecular dynamics and high level ab initio calculations. We show that both solvent molecules and counterions participate in the ETMD processes, and different ion associations have distinctive spectral fingerprints. Furthermore, ETMD spectra are sensitive to coordination numbers, ion solvent distances and solvent arrangemen

Dissociation and predissociation on coupled electronic potential energy surfaces: A three-dimensional wave packet dynamical study

Manthe U, Köppel H, Cederbaum LS. Dissociation and predissociation on coupled electronic potential energy surfaces: A three-dimensional wave packet dynamical study. JOURNAL OF CHEMICAL PHYSICS. 1991;95(3):1708-1720

Valence correlation bands of model oligomers of polyethylene: A Green’s function study by the band-Lanczos approach

The innermost valence electron levels of large molecular chains are subject to a strong breakdown of the orbital picture of ionization into particularly dense sets of shake-up lines with exceedingly small intensities, which give rise to correlation bands in the ionization spectrum. A suitable algorithm is required for a size-consistent investigation of such sets. In this work, we report the inclusion of the band-Lanczos approach in the final diagonalization step of a one-electron Green's function calculation in the algebraic diagrammatic construction scheme. From a first application to a series of oligomers CnH2n+2(n=2-9) converging to polyethylene, the C-2s correlation bands of large saturated hydrocarbons are shown to extend beyond 60 eV, and to represent, regardless of cross section effects, at least 20% of the total valence ionization intensity, and about 60% of the intensity found in the inner valence region [is an element of(b) = 18-70 eV]. With the band-Lanczos approach, the distribution of spectral intensity is nearly entirely recovered, with the exception of a tiny violation (2% for the n-nonane compound). (C) 1999 American Institute of Physics. [S0021-9606(99)30412-8]