Self-assembly of base-functionalized carbon nanotubes

We have studied the atomic and electronic structures, as well as the self-assembly mechanism of cytosine $(C)$ and guanine $(G)$ functionalized single-walled carbon nanotubes (SWNTs) by using ab initio calculations combined with empirical molecular dynamics (MD) simulations. Our results show that both the atomic and electronic structures of the SWNT can be drastically changed by the decoration with these bases, suggesting an effective pathway for band structure engineering. More interestingly, these functionalized SWNTs display self-assembly character and tend to form a ``ladder'' configuration as revealed in the MD simulations, which may find wide applications in fabricating nanodevices and nanocircuits.