The Zipper Mechanism of Nanotube Fusion:

Theory and Experiment


Mina Yoon, Seungwu Han, Gunn Kim, Sangbong Lee, Savas Berber, Eiji Osawa, Jisoon Ihm, Mauricio Terrones, Florian Banhart, Jean-Christophe Charlier, Nicole Grobert, Humberto Terrones, Pulickel M. Ajayan, David Tomanek

Intermediate states in the zipper process

Click on the thumbnail pictures to get the full-sized figures.

Details of the intermediate steps

One transformation cycle of the fusion process is represented as a sequence of structural diagrams in Figs. A and B, corresponding to the colored region in the 'front view' images above. In each structural drawing, a thick red emphasizes the central bond involved in the Stone-Wales reaction prior to the bond rotation. The bond after the rotation is identified by a thick black line. In the polygon network near the junction, hexagons are shown in white, heptagons in yellow, and octagons in blue.

  • Type A fusion (Fig. A):



  • Type B fusion (Fig. B):




    • More details about the elementary steps of the fusion process depicted in Figs. A and B are given in Tables A and B. In our notation used below, (l,m,n,k) or (lmnk) stands for the four polygons, l-,m-,n-, and k-membered rings, adjacent to the thick red line prior to the Stone-Wales transformation and the thick black line after the Stone-Wales transformation.


  • Table A. Reaction pattern of the SW transformation cycle.

     step

    Type A

    0 -> 1

    7766 -> 6677

    1 -> 2

    7766 -> 6677

    2 -> 3

    7766 -> 6677

    3 -> 4

    7766 -> 6677

    4 -> 5

    7767 -> 6678

    5 -> 6

    7766 -> 6677

    6 -> 7

    7766 -> 6677

    7 -> 8

    7766 -> 6677

    8 -> 9

    7766 -> 6677

    9 -> 10

    7766 -> 6677

    10 -> 11

    7866 -> 6777

    11 -> 12

    7766 -> 6677


  • Table B. Reaction pattern of the SW transformation cycle.

     step

    Type B

    0 -> 1

    7866 -> 6777

    1 -> 2

    7767 -> 6678

    2 -> 3

    7867 -> 6778

    3 -> 4

    7867 -> 6778

    4 -> 5

    7766 -> 6677

    5 -> 6

    7867 -> 6778

    6 -> 7

    7867 -> 6778

    7 -> 8

    7866 -> 6777

    8 -> 9

    7767 -> 6678


    • Details of the bond switching in the zipper mechanism (animations)

    Molecular Dynamics simulations at various temperatures of partly fused nanotubes (typeA) (animations)

    Last update: 12 August 2003.