Stability of pyruvic acid clusters upon slow electron attachment

0539383 - ÚFCH JH 2022 RIV GB eng J - Journal Article
Pysanenko, Andriy - Grygoryeva, Kateřina - Kočišek, Jaroslav - Kumar, Ragesh Thelakkadan Puthiyaveettil - Fedor, Juraj - Ončák, Milan - Fárník, Michal
Stability of pyruvic acid clusters upon slow electron attachment.
Physical Chemistry Chemical Physics. Roč. 23, č. 7 (2021), s. 4317-4325. ISSN 1463-9076. E-ISSN 1463-9084
R&D Projects: GA ČR(CZ) GA21-07062S; GA MŠMT(CZ) LTAUSA19031
Institutional support: RVO:61388955
Keywords : Electron energy levels * Energy dissipation * Mass spectrometry
OECD category: Physical chemistry
Impact factor: 3.945, year: 2021
Method of publishing: Limited access

Pyruvic acid represents a key molecule in prebiotic chemistry and it has recently been proposed to be synthesized on interstellar ices. In order to probe the stability of pyruvic acid in the interstellar medium with respect to decomposition by slow electrons, we investigate the electron attachment to its homomolecular and heteromolecular clusters. Using mass spectrometry, we follow the changes in the fragmentation pattern and its dependence on the electron energy for various cluster sizes of pure and microhydrated pyruvic acid. The assignment of fragmentation reaction pathways is supported by ab initio calculations. The fragmentation degree dramatically decreases upon clustering. This decrease is even stronger in the heteromolecular clusters of pyruvic acid with water, where the non-dissociative attachment is by far the strongest channel. In the homomolecular clusters, the dissociative channel leading to dehydrogenation is active over a larger electron energy range than in the isolated molecules. To probe the role of the self-scavenging effects, we explore the excited states of pyruvic acid. This has been done both experimentally, by using electron energy loss spectroscopy, and theoretically, by photochemical calculations. Data on both optically-allowed and forbidden states allow for the explanation of processes emerging upon clustering.

Permanent Link: http://hdl.handle.net/11104/0317082