A photoelectron circular dichroism (CD) study of the valence states of 2-amino-1-propanol (alaninol) in the gas phase is presented. The aim of the investigation is to reveal conformer population effects in the valence-state photoelectron spectrum. The experimental dispersion of the dichroic D parameter of valence states as a function of the photon excitation energy is compared with its theoretical value calculated by employing a multicentric basis set of B-spline functions and a Kohn-Sham Hamiltonian. The theoretical values are in very good agreement with the experimental data when the conformer population distribution is taken into account. Moreover, thanks to a comparison between experiment and theory, a clear assignment of the molecular orbital character and conformer geometry is given to the features of the photoelectron spectrum. This work indicates in a detailed experimental analysis that CD in photoelectron spectroscopy is an effective technique to disentangle the conformer assignment in photoelectron spectra.

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We have used density functional theory calculations, including a correction for the dispersive forces (DFT-D), to investigate the formation of a monolayer superstructure of uracil molecules adsorbed on the Au(100) surface. Our calculations provide insight into the interplay between lateral adsorbate adsorbate and vertical adsorbate substrate interactions, where we found that uracil adsorption to the surface is strongly dependent on the lateral interactions, particularly hydrogen bonding, although the first adsorbed molecule, before the formation of a uracil network, is covalently bonded to the surface. The self-assembly of the uracil network on the surface is mediated by proton transfer, and the ensuing charge separation stabilizes the geometry. Dispersive forces also play a role, and in particular, the introduction of a correction leads to flatter geometries with molecules lying parallel to the surface, thereby enhancing pi-pi stacking and hydrogen-bonding