In this study, novel measurements of negative ion formation in neutral potassium-neutral boronic acid collisions are reported in electron transfer experiments. The fragmentation pattern of phenylboronic acid is comprehensively investigated for a wide range of collision energies, i.e., from 10 to 1000 eV in the laboratory frame, allowing some of the most relevant dissociation channels to be probed. These studies were performed in a crossed molecular beam set up using a potassium atom as an electron donor. The negative ions formed in the collision region were mass analysed with a reflectron time-of-flight mass spectrometer. In the unimolecular decomposition of the temporary negative ion, the two most relevant yields were assigned to BO− and BO2−. Moreover, the collision-induced reaction was shown to be selective, i.e., at energies below 100 eV, it mostly formed BO−, while at energies above 100 eV, it mostly formed BO2−. In order to further our knowledge on the complex internal reaction mechanisms underlying the influence of the hybridization state of the boron atom, cyclohexylboronic acid was also investigated in the same collision energy range, where the main dissociation channel yielded BO2−. The experimental results for phenyl boronic acid are supported by ab initio theoretical calculations of the lowest unoccupied molecular orbitals (LUMOs) accessed in the collision process.
Authors
- Ana Lozano,
- Beatriz Pamplona,
- mgr inż. Tymon Kilich link open in new tab ,
- dr hab. inż. Marta Łabuda link open in new tab ,
- Mónica Mendes,
- João Pereira-da-Silva,
- Gustavo García,
- Pedro Gois,
- Filipe Ferreira Da Silva,
- Paulo Limão-Vieira
Additional information
- DOI
- Digital Object Identifier link open in new tab 10.3390/ijms20225578
- Category
- Publikacja w czasopiśmie
- Type
- artykuły w czasopismach
- Language
- angielski
- Publication year
- 2019