Theoretical study of fullerene derivatives: C28H4 and C28X4 cluster molecules

摘要

Based on the basic theory of C-28 cluster molecule proven by H. W. Kroto and the research findings of C-28's derivative such as Ti@C-28* and Mg@C-28, proven by T. Guo, B. I. Dunlap, O. D. Haberlen, and others, we examine the two series fullerene derivatives, C28H4 and C28X4 cluster molecules, which are formed by the skeleton of C-28 cluster molecule. In this work, we not only prove that C-28 cluster molecule belongs to the T-d symmetry structure and its ground state is (5)A(2) open-shell with four unpaired electrons, but also find that C-28 can easily react with single valence electron atoms, like hydrogen atom and halogen atoms, to be formed to stable fullerene derivatives, C28H4 and C28X4 cluster molecules (X = F, Cl, Br, I). The PM3 semiempirical molecular orbital method from G94W and Hyperchem program packages were applied very well in these fullerene derivatives. According to the results presented herein, we obtain the structures of geometrical optimization, ionization potential energy gap, heat of formation, atomization energy, and vibration frequency data of the C28H4 and C28X4 cluster molecules. The above calculation data confirm that these unknown fullerene derivatives are stable molecules; the stable behavior resembles the 1,3,5,7-tetrahaloadamantane molecules. It is quite possible that they can be synthesized experimentally in the near future. (C) 1998 John Wiley & Sons, Inc. [References: 43]