Journal ArticleWhy do A·T and G·C self-sort? Hückel aromaticity as a driving force for electronic complementarity in base pairingZhang, Yu; Wu, Chia-Hua; Wu, Judy I-ChiaDensity functional theory computations and block-localized wavefunction analyses for 57 hydrogen-bonded base pairs document excellent linear correlation between the gas-phase association energies and the degree of aromaticity gain of paired bases ( r = 0.949), challenging prevailing views of factors that underlie the proposed electronic complementarity of A·T(U) and G·C base pairs. Base pairing interactions can polarize the π-electrons of interacting bases to increase (or decrease) cyclic 4 n + 2π electron delocalization, resulting in aromaticity gain (or loss) in the paired bases, and become strengthened (or weakened). The potential implications of this reciprocal relationship for improving nucleic acid force-fields and for designing robust unnatural base pairs are discussed.2018-01-0110081327Organic & Biomolecular Chemistry1477-0520https://doi.org/10.1039/C8OB01669K1751370National Science Foundation