Resonances and Dissociative Electron Attachment in HNCO

0494626 - ÚFCH JH 2019 RIV US eng J - Journal Article
Zawadzki, Mateusz - Čížek, M. - Houfek, K. - Čurík, Roman - Ferus, Martin - Civiš, Svatopluk - Kočišek, Jaroslav - Fedor, Juraj
Resonances and Dissociative Electron Attachment in HNCO.
Physical Review Letters. Roč. 121, č. 14 (2018), č. článku 143402. ISSN 0031-9007. E-ISSN 1079-7114
R&D Projects: GA ČR GA17-04844S; GA ČR(CZ) GA18-02098S; GA ČR GJ16-10995Y; GA ČR GA17-05076S; GA MŠMT EF16_019/0000778
Institutional support: RVO:61388955
Keywords : Electron energy analyzers * Potential energy * Electrons
OECD category: Physical chemistry
Impact factor: 9.227, year: 2018

In a combined experimental and theoretical study, we probe the dissociative electron attachment in isocyanic acid HNCO. The experimental absolute cross section for the NCO- fragment shows a sharp onset and fine structures near the threshold. The autoionizing state responsible for the dissociative attachment is found in both the R-matrix calculation and using analytic continuation in the coupling constant. The involved A′ resonance has a mixed π∗/σ∗ character along the dissociating bond and thus combines the effects of nonzero electron angular momentum and dipole-supported states. This leads to unusual behavior of its width at various geometries. Because the potential energy gradient of the autoionizing state points essentially in the direction of the NH bond, nuclear dynamics can be described by a one-dimensional nonlocal model. The results agree with the experiment both quantitatively and qualitatively. The present system may be a prototype for interpretation of the dissociative electron attachment process in a number of other polyatomic systems.
Permanent Link: http://hdl.handle.net/11104/0287738