01741nas a2200217   4500008004100000245015100041210006900192260000800261490000800269520090500277100002101182700002101203700002301224700003001247700002201277700002101299700002501320700002901345700002101374856012801395       2010                        eng d00aNon-covalent interactions in extended systems described by the effective fragment potential method: theory and application to nucleobase oligomers0 aNoncovalent interactions in extended systems described by the ef  cNOV0 v1143 aThe implementation of the effective fragment potential (EFP) method within the Q-CHEM electronic structure package is presented. The EFP method is used to study noncovalent π-π and hydrogen-bonding interactions in DNA strands. Since EFP is a computationally inexpensive alternative to high-level ab initio calculations, it is possible to go beyond the dimers of nucleic acid bases and to investigate the asymptotic behavior of different components of the total interaction energy. The calculations demonstrated that the dispersion energy is a leading component in π-stacked oligomers of all sizes. Exchange-repulsion energy also plays an important role. The contribution of polarization is small in these systems, whereas the magnitude of electrostatics varies. Pairwise fragment interactions (i.e., the sum of dimer binding energies) were found to be a good approximation for the oligomer energy.1 aGhosh, Debashree1 aKosenkov, Dmytro1 aVanovschi, Vitalii1 aWilliams, Christopher, F.1 aHerbert, John, M.1 aGordon, Mark, S.1 aSchmidt, Michael, W.1 aSlipchenko, Lyudmila, V.1 aKrylov, Anna, I.  uhttps://library.ncl.res.in/content/non-covalent-interactions-extended-systems-described-effective-fragment-potential-method