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arXiv · 2106.10518

A Doorway mechanism for Electron Attachment Induced DNA Strand Break

Jishnu Narayanan S J·Divya Tripathi·Achintya Kumar Dutta
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Abstract

We report a new doorway mechanism for the dissociative electron attachment to genetic materials. The dipole-bound state of the nucleotide anion acts as the doorway for electron capture in the genetic material. The electron gets subsequently transferred to a dissociative {\sigma}* type anionic state localized on a sugar-phosphate or a sugar-nucleobase bond, leading to their cleavage. The electron transfer is mediated by the mixing of electronic and nuclear degrees of freedom. The cleavage rate of the sugar-phosphate bond predicted by this new mechanism is higher than that of the sugar-nucleobase bond breaking, and both processes are considerably slower than the formation of a stable valence-bound anion. The new mechanism explains the relative rates of electron attachment induced bond cleavages in genetic materials.

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Jishnu Narayanan S J, Divya Tripathi, Achintya Kumar Dutta. 2021-06-19. A Doorway mechanism for Electron Attachment Induced DNA Strand Break. https://arxiv.org/abs/2106.10518

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