G. Dolgonos "Molecular mechanics and molecular dynamics study of the complexes of fullerenes and nanotubes"



Abstract


Fullerenes and carbon nanotubes represent an exciting class of molecules. Their hollow structures enable the formation of endohedral complexes with atoms, ions or molecules which may find potential applications. The most fascinating proposed applications involve endohedral fullerene complexes. Being buried inside one another, fullerenes can also form nested structures like C60@C240, which are characterized by high thermal stability. Carbon nanotubes are more promising candidates for the industrial applications than fullerenes because of their excellent physical properties (i.e. high stiffness, electrical and thermal conductivity, etc.). In addition, the use of nanotubes as hydrogen containers have been proposed. In this work, several complexes of fullerenes and nanotubes have been studied by means of molecular mechanics, molecular dynamics and/or quantum mechanics in order to:

  1. determine which guest molecules can be inserted inside and form stable complexes with fullerenes
  2. get an insight into the forces driving the formation of nested fullerenes
  3. propose which outer fullerene cages are most suitable for the stabilization of the unstable inner C20 cage
  4. estimate the ability of carbon nanotubes to store molecular hydrogen by physisorption
  5. analyze the stabilization of linear carbon atom chains inside carbon nanotubes.

In view of the great amount of the literature on fullerenes and nanotubes, only works directly pertaining to the subject of the thesis are discussed in Chapter 1. In Chapter 2, the applied methods of calculation are described. Then, the results of molecular mechanics calculations of endohedral fullerene complexes with small molecules are presented in Chapter 3. Chapter 4 is devoted to the molecular mechanics and molecular dynamics study of nested fullerenes while analogous study of hydrogen storage in carbon nanotubes is described in Chapter 5. In Chapter 6, the molecular mechanics, molecular dynamics and ONIOM study of polyyne and polyene carbon chains inside (5,5)nanotubes are described. The computational details, description of the forcefields used and list of abbreviations are presented in Appendix.