Potassium-uracil/thymine ring cleavage enhancement as studied in electron transfer experiments and theoretical calculations.

نویسندگان

  • D Almeida
  • M-C Bacchus-Montabonel
  • F Ferreira da Silva
  • G García
  • P Limão-Vieira
چکیده

We report experimental and theoretical studies on ring cleavage enhancement in collisions of potassium atoms with uracil/thymine to further increase the understanding of the complex mechanisms yielding such fragmentation pathways. In these electron transfer processes time-of-flight (TOF) negative ion mass spectra were obtained in the collision energy range 13.5-23.0 eV. We note that CNO(-) is the major ring breaking anion formed and its threshold formation is discussed within the collision energy range studied. Such a decomposition process is supported by the first theoretical calculations to clarify how DNA/RNA pyrimidine base fragmentation is enhanced in electron transfer processes yielding ion-pair formation.

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عنوان ژورنال:
  • The journal of physical chemistry. A

دوره 118 33  شماره 

صفحات  -

تاریخ انتشار 2014