par Cauet, Emilie 
;Bogatko, Stuart ;Liévin, Jacques ;De Proft, Frank;Geerlings, Pau̧l
Référence The Journal of Physical Chemistry. B, 117, 33, page (9669-9676)
Publication Publié, 2013-08
;Bogatko, Stuart ;Liévin, Jacques ;De Proft, Frank;Geerlings, Pau̧lRéférence The Journal of Physical Chemistry. B, 117, 33, page (9669-9676)
Publication Publié, 2013-08
Article révisé par les pairs
| Résumé : | Low energy electron-attachment-induced damage in DNA, where dissociation channels may involve multiple bonds including complex bond rearrangements and significant nuclear motions, is analyzed here. Quantum mechanics/molecular mechanics (QM/MM) calculations reveal how rearrangements of electron density after vertical electron attachment modulate the position and dynamics of the atomic nuclei in DNA. The nuclear motions involve the elongation of the P-O (P-O3′ and P-O5′) and C-C (C3′-C4′ and C4′-C5′) bonds for which the acquired kinetic energy becomes high enough so that the neighboring C3′-O3′ or C5′-O5′ phosphodiester bond may break almost immediately. Such dynamic behavior should happen on a very short time scale, within 15-30 fs, which is of the same order of magnitude as the time scale predicted for the excess electron to localize around the nucleobases. This result indicates that the C-O phosphodiester bonds can break before electron transfer from the backbone to the base. © 2013 American Chemical Society. |
