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Interactions in concentric carbon nanotubes: the radius vs the chirality angle contributions
Luca Bellarosa1, Evangelos Bakalis, Manuel Melle-Franco
1Dipartimento di Chimica G. Ciamician, Università di Bologna, V. F. Selmi 2, 40126 Bologna, Italy.
Nano Letters
|September 14, 2006
Summary
Guest-host interactions in double-wall carbon nanotubes (DWCNTs) are primarily governed by the difference in radii (Deltar) and chirality angle mismatch (Deltatheta). New functions predict minimum energy structures for DWCNTs based on these parameters.
Area of Science:
- Materials Science
- Nanotechnology
- Computational Chemistry
Background:
- Guest-host interactions in multiwall carbon nanotubes (MWCNTs), especially double-wall carbon nanotubes (DWCNTs), are crucial for their properties.
- These interactions are influenced by geometric parameters like radii difference and chirality mismatch.
Purpose of the Study:
- To investigate the relationship between geometric parameters and the minimum energy structures of DWCNTs.
- To develop predictive functions for constructing stable DWCNT configurations.
Main Methods:
- Calculated minimum energy structures for 198 distinct DWCNT configurations.
- Developed two empirical functions based on the difference in radii (Deltar) and chirality angle mismatch (Deltatheta) to fit the calculated data.
Main Results:
- Identified Deltar and Deltatheta as primary factors governing DWCNT energy structures.
- Established that cross terms between Deltar and Deltatheta are significant.
- Rationalized the derived functions using fundamental physical principles.
Conclusions:
- The developed functions accurately model the minimum energy configurations of DWCNTs.
- These functions provide a valuable tool for the rational design and construction of multiwall nanotubes with desired properties.
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