Abstract: MATH/CHEM/COMP 2002, Dubrovnik,
June 24-29, 2002
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Energetics and
topology of Polyhex NanoTubes
Mircea V. Diudea1, Silviu T. Balaban2, Miljenko Primorac3, and Ante Graovac4,5 1Faculty of Chemistry and Chemical
Engineering, Babes‑Bolyai University, RO-3400 Cluj, Romania 2 Forschungszentrum Karlsruhe, Institut fuer
Nanotechnologie, Karlsruhe, Germany 3Faculty of Forestry, University
of Zagreb, Svetosimunska 25, HR-10000 Zagreb, Croatia 4Ruđer Bošković
Institute, POB 180, HR-10002 Zagreb, Croatia 5Faculty of Natural Sciences, Mathematics and
Education, University of Split, Nikole Tesle 12, HR-21000 Split, Croatia Single
wall nanotubes are generated by modifying a cylindrical square tiled lattice,
in a manner similar to that used previously by us in generating polyhex tori.1-5
This way of building enables the orientation of their bonds, resulting a
large variety of tubes: crenellated (i.e.,
armchair, or anthracenoid), zigzag (or phenanthrenoid) non-chiral objects as
well as variously twisted (i.e.,
chiral) tubes. Their energetic stability was evaluated by MM+
calculation. Twisting appears to relax the total energy/atom, which, in large
diameter tubes, approaches that in the graphite sheet. Spectral analysis
envisages a pallet of shells ranging from the closed to open and metallic
ones. This behavior is rationalized in terms of the pattern square net
dimensions. Topological characterization includes the Wiener index (i.e., the sum of all distances in a
graph ) and the spiral code.
1 M. V. Diudea, A. Graovac, Generation and Graph-Theoretical
Properties of C4-Tori. Commun.
Math. Comput. Chem. (MATCH) 44
(2001) 93-102. 2 M. V. Diudea, I. Silaghi-Dumitrescu, B. Parv, Toranes versus
Torenes. Commun. Math. Comput. Chem.
(MATCH) 44 (2001) 117-133. 3 M. V.
Diudea, P. E. John, Covering Polyhedral Tori. Commun. Math. Comput. Chem. (MATCH) 44 (2001) 103-116. 4 M. V. Diudea, E. C. Kirby, The
Energetic Stability of Tori and Single-wall Tubes. Fullerene Sci. Technol. 9 (2001) 445-465. 5. M. V. Diudea, Toroidal
Graphenes from 4-Valent Tori. Bull.
Chem. Soc. Japan, 75 (2002) 587-592. |