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arXiv · 2602.21378

The Effect of Base-Pairing on the Shape Resonances of Nucleobases

Jishnu Narayanan S J·Divya Tripathi·Idan Haritan·Amitava Adhikary·Bhawana Pandey·Achintya Kumar Dutta
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Abstract

In this work, we have studied the effect of base-pairing on the shape resonances of guanine and cytosine nucleobases. Among the seven {\pi}* resonances we identified in the guanine-cytosine (GC) anion radical, three were centered on cytosine, and the remaining were guanine-centered. Relative to the isolated bases, upon base pair formation, the cytosine resonances were red shifted, while the guanine-centered states showed an opposite trend - where their energy was blue shifted. In addition to the electronic interactions, geometric distortion and basis set superposition error plays a crucial role in the resonance positions and widths of the GC radical anion. The electronic interaction from the complementary base seems to have a larger effect on the stabilization of the anionic resonances than the surrounding environment.

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Jishnu Narayanan S J, Divya Tripathi, Idan Haritan, Amitava Adhikary, Bhawana Pandey, Achintya Kumar Dutta. 2026-02-24. The Effect of Base-Pairing on the Shape Resonances of Nucleobases. https://arxiv.org/abs/2602.21378

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