title: The role of the shape resonance state in low energy electron induced single strand break in 2'-deoxycytidine-5'-monophosphate.
abstract: Low energy electron (LEE) induced single strand break (SSB) has been studied for 2'-deoxycytidine-5'-monophosphate (5'-dCMPH) molecules in the gas phase by means of ab initio electronic structure methods and local complex potential based time-dependent wavepacket quantum mechanical calculations. We have found that the LEE attachment to this cytidine nucleotide results in the formation of a transient metastable anion. The results obtained here show that the electron attachment takes place at the cytosine nucleobase center and within 18-20 fs, the LEE transfers to the σ* orbital of the sugar-phosphate 5' C-O bond. The characteristic electron attachment cross section spectrum is found at ∼1 eV, which is in good agreement with the available experimental observations. Quantum mechanical tunneling of the 5' C-O bound vibrational energy levels may contribute to SSB only above 1.5 eV energy regimes.
authors.affiliation: Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati, India. msarma@iitg.ernet.in.
authors.forename: Renjith
authors.initials: R
authors.lastname: Bhaskaran
authors.forename: Manabendra
authors.initials: M
authors.lastname: Sarma
mesh_terms: D000838:Anions / Q000737:chemistry; D053904:DNA Breaks, Single-Stranded; D003843:Deoxycytidine Monophosphate / Q000737:chemistry*; D004583:Electrons; D005740:Gases / Q000737:chemistry; D008958:Models, Molecular; D011789:Quantum Theory; D013816:Thermodynamics
chemical_list: D000838:Anions; D005740:Gases; D003843:Deoxycytidine Monophosphate