Diffraction in resonant electron scattering from helical macromolecules: A- and B-type DNA
نویسندگان
چکیده
We elaborate our theoretical framework to treat low-energy electron scattering from helical macromolecules. A model of simple scatterers organized into a helical structure is proposed with application to base-pair arrangements in DNA. We extend our analysis to A-type DNA as well as nonperiodic arrangements in B-type DNA. Diffraction patterns due to base-pair spacing are observed under all conditions. We discuss the role of electron diffraction in electron attachment to the bases leading to the formation of shape and core-excited resonances. The decay of such transient anions into dissociative-state channels producing DNA strand breaks is also described. We find A-type DNA to be much more sensitive to low-energy electrons than B type.
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تاریخ انتشار 2004