Interaction Between NO2 and an Elongated Fullerene C60

The adsorptions of several molecules of NO2 (considering their spin-states) on an elongated fullerene [i.e., a very short (8, 0) closed-cap single-walled carbon nanotube] were examined by computing their binding energies through spin-unrestricted density functional theory methods. While NO2 ((2)A(1)) is weakly adsorbed (binding energies of ca. 0.07 eV), the (4)A(2) spin-state leads to form the most energy-favored complex. As a result of the new attachments, transitions from metallic to semiconducting states were observed. These results show, on one hand, dependence on the selection of a suitable nanotube model (e.g., closed caps) and, on the other hand, the importance for accounting different spin-states for studying interactions with paramagnetic molecules.