A cytosine-assisted carbon nanotubes junction: DFT studies

作者：Mirzaei Mahmoud^*; Meskinfam Masoumeh; Yousefi Mohammad

来源：Superlattices and Microstructures, 2012, 52(2): 158-164.

DOI：10.1016/j.spmi.2012.04.018

• Carbon nanotube
• Cytosine
• Junction
• Density functional theory

Since nucleobase-functionalized carbon nanotubes (CNTs) are important in the biological applications; the junction of a pair of CNTs through a bridging cytosine linkage is investigated based on density functional theory (DFT) calculations. In the exact model of study, the CNTs are bound to N-1 and C-5 atomic sites of cytosine to make possible the CNT-cytosine-CNT model. To systematically investigate the purpose, the models of original CNT, original cytosine, and primary models of cytosine-CNT in which one CNT is only bound to NI or C5 atomic site of cytosine are also considered. The results of dipole moments and binding energies indicated that the CNT-cytosine-CNT model is the most stable one among all three possible models cytosine-functionalized CNT. The values of energy gaps indicated that the conducting properties of primary cytosine-CNT models are not changed referring to the original CNT but better conductivity could be observed for the CNT-cytosine-CNT model. The values of evaluated quadrupole coupling constants indicated that the electronic densities of nitrogen and oxygen atoms of cytosine detect notable affects during the functionalization processes by the zigzag CNTs and the oxygen atom of CNT-cytosine-CNT model could be proposed as the most proper interacting site of cytosine among other functionalized zigzag models and also the original cytosine. However, the changes of quadrupole coupling constants for the atoms of cytosine are almost negligible during the functionalization processes by the armchair CNTs.

• 出版日期2012-8