2025/06/14 by Soumya Ghosh, Narayan Kundu, Ghosh, Soumya +5 · 1 citation
Earth and Planetary Sciences · Engineering · Physics and Astronomy · #Atomic Physics (physics.atom-ph) #Atomic and Molecular Clusters (physics.atm-clus) #Chemical Physics (physics.chem-ph) #FOS: Physical sciences #High-pressure geophysics and materials #Laser-induced spectroscopy and plasma #Nuclear Physics and Applications
paper · pdf · doi:10.48550/arxiv.2506.12528
openalex publication_date 2025/06/14 · openalex created_date 2025/10/13 · openalex updated_date 2026/07/29
In this study, we examine the interactions of low- to intermediate-energy electrons (0-45 eV) with carbonyl sulfide (OCS). These collisions lead to the formation of several anionic fragments, including C-, O-, S-, and SO-. When the incident electron energy is below the first ionization potential of the molecule, dissociative electron attachment (DEA) process dominates, primarily yielding O- and S- fragments. At higher energies, beyond the ionization potential, ion-pair dissociation (IPD) becomes the dominant process, resulting in the emergence of additional fragments such as C- and SO-. This leads to an increasingly intricate mechanism, necessitating a detailed analysis to elucidate the ion-pair dissociation pathways. The absolute cross section for S- ions has been determined using the well-established relative flow technique. Theoretical cross sections are calculated using the multi-configurational time-dependent hartree (MCTDH) method, with each potential energy curve obtained from equation-of-motion coupled-cluster singles and doubles (EOM-CCSD) calculations. The computed values are in excellent agreement with the experimental data. The analysis reveals contributions from both linear and bent anionic resonant states. Due to low count rates, only relative cross section curves have been obtained for the O- and SO- ions. At higher energies, the ion pair thresholds are evaluated using the Wannier threshold law, yielding values consistent with those derived from thermochemical data.