Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Are multi-quasiparticle interactions important in molecular ionization?   Photo-emission spectroscopy directly probes individual electronic states,
ranging from single excitations to high-energy satellites, which simultaneously
represent multiple quasiparticles (QPs) and encode information about electronic
correlation. First-principles description of the spectra requires an efficient
and accurate treatment of all many-body effects. This is especially challenging
for inner valence excitations where the single QP picture breaks down. Here, we
provide the full valence spectra of small closed-shell molecules, exploring the
independent and interacting quasiparticle regimes, computed with the
fully-correlated adaptive sampling configuration interaction (ASCI) method. We
critically compare these results to calculations with the many-body
perturbation theory, based on the $GW$ and vertex corrected $GW\Gamma$
approaches. The latter explicitly accounts for two-QP quantum interactions,
which have been often neglected. We demonstrate that for molecular systems, the
vertex correction universally improves the theoretical spectra, and it is
crucial for accurate prediction of QPs as well as capturing the rich satellite
structures of high-energy excitations. $GW\Gamma$ offers a unified description
across all relevant energy scales. Our results suggest that the multi-QP regime
corresponds to dynamical correlations, which can be described via perturbation
theory.

22
The categories of this paper are: chao-dyn
33
The categories of this paper are: plasm-ph
10
The categories of this paper are: q-bio
6
The categories of this paper are: astro-ph
7
The categories of this paper are: hep-th
24
The categories of this paper are: dg-ga
29
The categories of this paper are: funct-an
34
The categories of this paper are: chem-ph
23
The categories of this paper are: solv-int
18
The categories of this paper are: econ
36
The categories of this paper are: cmp-lg
25
The categories of this paper are: patt-sol
11
The categories of this paper are: hep-lat
9
The categories of this paper are: nlin
35
The categories of this paper are: mtrl-th
4
The categories of this paper are: cond-mat