▎ 摘 要
Structures and interaction energies of complexes formed by Watson-Crick base pairs and carbon surfaces (nanotubes and graphene) are investigated using the DFT M05-2X and MP2 quantum chemical computational methods. High structural flexibility of the complexes is demonstrated. Structures with approximately parallel and perpendicular orientations of the base pairs and the nanotube main axis are revealed. The complexes formed by the GC base pair and large-diameter zigzag nanotubes with the perpendicular orientation of the two systems are found to be the lowest energy configurations. Decomposition of the interaction energies into two-body contributions is applied to explain the nature of the interaction. The question of how the interaction between a base pair and a carbon surface affects the H-bonding between the nucleobases in the pair is elucidated. (C) 2014 Elsevier B.V. All rights reserved.