Hydrated Formic Acid Clusters and their Interaction with Electrons

Chemphyschem. 2024 Feb 19:e202400071. doi: 10.1002/cphc.202400071. Online ahead of print.ABSTRACTWe investigate ion formation in hydrated formic acid (FA) clusters upon collision with electrons of variable energy, focusing on electron ionization at 70 eV (EI) and low-energy (1.5-15 eV) electron attachment (EA). To uncover details about the composition of neutral clusters, we aim to elucidate the ion formation processes in FAM·WN clusters initiated by interaction with electrons and determine the extent of cluster fragmentation. EI predominantly produces protonated [FAm+H]+ ions, and in FA-rich clusters, the stable ring structures surrounding H3O+ ions are formed. In contrast, EA leads to a competition between the formation of intact [FAm·Wn]- and dissociated [FAm·Wn-H]- fragment ions, influenced by the cluster size, level of hydration, and electron energy. Our findings reveal a predisposition of lowenergy EA towards forming [FAm·Wn]-, while higher electron energies tend to favor the formation of [FAm·Wn-H]- due to intracluster ion-molecule reactions. The comparison of positive and negative ion spectra suggests that the mass spectra of FA-rich clusters may indicate their actual size and composition. On the other hand, the more weakly bound water evaporation from the clusters depends strongly on the ionization. Thus, for the hydrated clusters, the neutral cluster size can hardly be estimated from the mass spectra.PMID:38372591 | DOI:10.1002/cphc.202400071

Source: Chemphyschem - February 19, 2024 Category: Chemistry Authors: Kevin Li Jozef Ďurana Barbora Koc ábková Andrij Pysanenko Yihui Yan Milan On čák Michal F árník Jozef Lengyel Source Type: research