Abstract
We investigate the optimal orientations and positions of tubular fullerene molecules C70, C80 and C90 encapsulated in single-walled carbon nanotubes (SWCNTs). We find that increasing the tube radius leads to the following succession of energetically stable regimes: 1) lying molecules positioned on the tube's long axis, 2) tilted molecules on the tube's long axis and 3) lying molecules shifted away from the tube's long axis. In the case of C70 and C80 molecules, standing on-axis configurations also occur. Our findings are relevant for the possible application of molecular-orientation-dependent electronic properties of fullerene nanopeapods.
Acknowledgments
This work was financially supported by the Research Foundation - Flanders (FWO-Vl). B. V. is a Postdoctoral Fellow of the Research Foundation–Flanders (FWO-Vl).