AI Article Synopsis
- The study examines the electronic interactions of stacked nucleic acid bases (adenine, thymine, cytosine, and uracil) in their excited states within homodimer and trimer complexes.
- The research compares these interactions in A-DNA and B-DNA conformations, highlighting that electronic interactions are stronger in A-DNA.
- It concludes that while orbital-overlap interactions generally play a minor role in electronic coupling, significant coupling is observed only in states resulting from (pi --> pi*) transitions.
Article Abstract
The nature of the electronic interactions of the stacked nucleic-acid bases (adenine, thymine, cytosine, and uracil) in homodimer and -trimer complexes in their electronically excited states was investigated and analysed in terms of orbital-overlap and Coulombic interactions. The mutual orientations of the adjacent bases were selected so as to correspond to the A- and B-DNA conformations. The extent of the electronic interaction is larger for the former conformation. It is shown that the orbital-overlap interactions at the distance of two bases relevant to the DNA structure do not contribute significantly to the overall electronic coupling. Only the states which are caused by the (pi --> pi*) transitions manifest an electronic coupling.
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| http://dx.doi.org/10.1039/b806323k | DOI Listing |
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