Peak Broadening in Photoelectron Spectroscopy of Amorphous Polymers: the Leading Role of the Electrostatic Landscape
arXiv:2505.05072 · doi:10.1021/acs.jpclett.3c02640
Abstract
The broadening in photoelectron spectra of polymers can be attributed to several factors, such as light source spread, spectrometer resolution, finite lifetime of the hole state, and solid-state effects. Here, for the first time, we set up a computational protocol to assess the peak broadening induced for both core and valence levels by solid-state effects in four amorphous polymers by using a combination of density functional theory, many-body perturbation theory, and classical polarizable embedding. We show that intrinsic local inhomogeneities in the electrostatic environment induce a Gaussian broadening of -~eV in the binding energies of both core and semi-valence electrons, corresponding to a full width at half maximum (FWHM) of -~eV for the investigated systems. The induced broadening is larger in acrylate- than in styrene- based polymers, revealing the crucial role of polar groups in controlling the roughness of the electrostatic landscape in the solid matrix.