Biopolym. Cell. 2005; 21(4):351-357.
http://dx.doi.org/10.7124/bc.0006FC
Molecular Biophysics
Quantum-chemical modelling radiation damage of DNA components during inelastic interaction with slow electrons. Desoxyribose irradiation
1Minaev B. F., 1Yevtukhov Y. V., 2Minaeva V. A.
  1. Cherkasy State Technological University
    460, Shevchenko Blvd., Cherkassy, Ukraine, 18006
  2. B. Khmelnyckyy Cherkasy National University
    81, Shevchenko Blvd., Cherkassy, Ukraine, 18031

Abstract

The total energies and heat of formation of intermediates of the deoxyribose dissociation during its interaction with a monochromatic electron beam have been calculated by the method of molecular orbitals of self-consistent field (SCF) with AM1 approximation. Dissociative attachment of slow electrons begins at the energy close to zero, although the electron affinity of deoxyribose is negative (near –2 eV), which points to the tunnelling mechanism of the reaction. The calculation of energies for all channels of dissociation of anion halfproducts closely fits the experiment for the effective cross section of the dissociative electron capture.
Keywords: 2-deoxy-β-D-ribose, AMI method, dissociation energy, anion products, electron
Full text: (PDF, in Russian)

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