Electron driven reactions in sulphur containing analogues of uracil: the case of 2-thiouracil
- Resource Type
- Authors
- M. T. do N. Varella; F. Kossoski; Janina Kopyra; Hassan Abdoul-Carime
- Source
- Physical Chemistry Chemical Physics
Physical Chemistry Chemical Physics, Royal Society of Chemistry, 2014, 16 (45), pp.25054-25061. ⟨10.1039/c4cp03544e⟩
- Subject
- Models, Molecular
Thiocyanate
Molecular Conformation
General Physics and Astronomy
Electrons
Electron
Hydrogen atom
Photochemistry
Thiouracil
3. Good health
Ion
chemistry.chemical_compound
chemistry
Fragmentation (mass spectrometry)
Computational chemistry
Molecule
Molecular orbital
[PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph]
Physical and Theoretical Chemistry
ComputingMilieux_MISCELLANEOUS
- Language
- ISSN
- 1463-9084
1463-9076
The fragmentation of 2-thiouracil (TU) molecules induced by low energy (12 eV) electrons is investigated experimentally and theoretically. It is observed that most of the damage is localised at the sulphur site and in particular visible via the production of the thiocyanate, SCN(-), anion. Similar to the canonical nucleobases the loss of the hydrogen atom is a predominant dissociation channel already at the subexcitation energies. The theory shows that for incident electron energies below 3 eV dissociative electron attachment is initiated by shape resonances implicating the π* molecular orbitals. It may also arise from the dipole bound supported state as illustrated by the production of the SCN(-), S(-) and (TU-S)(-) fragments observed close to 0 eV but also the formation of (TU-H)(-) species at 0.7 and 1 eV.