| The present thesis concerns the understanding of the formation mechanism of carbon nanoclusters including fullerene molecules and single-walled carbon nanotubes and the new density-functional based tight-binding method parameter development for Ti, Fe, Co and Ni. It consists of nine chapters.;The first Chapter is the introduction of semiempirical methods as well as Hartree-Fock theory and density functional theory. In Chapter 2, the benchmarking of C-C DFTB parameters on fullerene isomers are presented (Guishan Zheng, Stephan Irle, Keiji Morokuma, Chem. Phys. Lett. (2005) 412, 210). Followed in chapter 3 are the new DFTB parameters for Ni, Fe, Co and Ni. From Chapter 4 to Chapter 7, the details of formation of fullerene molecules from open-ended single-walled carbon nanotubes molecules and randomly positioned C2 molecules are expounded. The general features and the possible ways for the growth of fullerene molecules are discussed (Stephan Irle, Zhi Wang, Guishan Zheng and Keiji Morokuma, J. Chem. Phys, (2006) in press; Stephan Irle, Guishan Zheng, Zhi Wang and Keiji Morokuma, J. Phys. Chem. B, (2006) 110, 14531; Stephan Irle, Guishan Zheng, Marcus Elstner and Keiji Morokuma, in "Theory and Applications of Computational Chemistry: The First 40 Years", Ed. C. E. Dykstra, G. Frenking, K. S. Kim, G. E. Scuseria, Elsevier (2005) p. 875; Guishan Zheng, Stephan Irle and Keiji Morokuma, J. Chem. Phys. (2005) 122, 01470; Guishan Zheng, Stephan Irle, Marcus Elstner and Keiji Morokuma, J. Phys. Chem. A (2004) 108, 3182; Stephan Irle, Guishan Zheng, Marcus Elstner and Keiji Morokuma, Nano Lett. (2003) 3, 1657; Stephan Irle, Guishan Zheng, Marcus Elstner and Keiji Morokuma, Nano Lett. (2003) 3, 465). In Chapter 8, the first step toward understanding the role of Fe clusters during the growth of single-walled carbon nanotubes molecules is reported (Guishan Zheng, Stephan Irle and Keiji Morokuma, J. Nano. Sci. Tech. (2006) 6, 1259). In the final Chapter 9, the theoretical study of functionalization of single-walled carbon nanotubes molecules is discussed (Guishan Zheng, Zhi Wang, Stephan Irle and Keiji Morokuma, resubmitted to JACS). The origin of the reaction energy is explained. |
