PROBING THE STACKING INTERACTION IN NUCLEIC ACIDS

这个子项目是许多研究子项目中的一个 由NIH/NCRR资助的中心赠款提供的资源。子项目及 研究者（PI）可能从另一个NIH来源获得了主要资金， 因此可以在其他CRISP条目中表示。所列机构为 研究中心，而研究中心不一定是研究者所在的机构。 而从头算电子结构方法是成功的计算涉及核酸碱基之间的氢键，他们失败时，应用到堆叠相互作用。失败已被归因于电子相关性不足，这意味着基组的扩展可能会改善结果。我想探索一种概念上不同的方法来堆叠和计算涉及核酸碱基和碱基对的氢化和/或脱氢基团的复合物。将在B3 LYP/aug-cc-pVDZ水平进行探索性计算。尽管使用一个相当温和的基础设置为这个问题，计算将需要大量的计算资源，由于大量的原子在所考虑的集群。如果成功，探索性计算将扩展到包括碱基之间的磷酸-糖连接，并计算小寡核苷酸的结构。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Whereas the ab-initio electronic structure methods are successful in calculations involving hydrogen bonding between nucleic acids bases, they fail when applied to stacking interaction. That failure has been attributed to the inadequate ellectronic correlations and it is implied that expansion of the basis set may improve the results. I would like to explore a conceptually different approach to stacking and perform calculations for complexes involving hydrogenated and/or dehydrogenated radicals of nucleic acid bases and base pairs. The exploratory calculations will be performed at the B3LYP/aug-cc-pVDZ level. Inspite of using a rather modest basis set for this problem, the calculations will require significant computational resources due to the large number of atoms in the considered clusters. If successful, the exploratory calculations will be extended to include the phosphate-sugar links between the bases and to calculate structures of small oligonucleotides.