Summary: | 碩士 === 淡江大學 === 化學學系 === 85 === During the last decade, tile study ill fallerenes has rapidly become one of the most interested in chemistly, physics and material science. Since they contain π electrons and provide more chemical reactivity than other carbon molecules. In this thesis, a). the intramolecular skeletal rearrangments between C60, C78 and their isomers have been proposed. b). a semiempirical (AM1) calculation on the structures and stabilities of the isomers of filllerene derivatives C60O and C70O is carried out and their ozonolysis reaction mechanism as well as thermodynamics are studied. c). the molecular dynamics and semiempirical method are used to simulate the room temperature reactivates of C60O and C70O.
For the analysis of the fullerene structure. The 2-D schlegel diagrams will symmetry for fulllerene are used to find the possible reaction mechanism in the geometry interconversion. The results suggest that C60(Ih) and C76 (Td) are the global minimum structure of C60 (5 isomers) and C76 (3 isomers) respectively.
According to the geometrical structure of C60 (5-6 bond and 6-6 bond), the two isomers of C60O formed by an oxygen atom bridging across a C-C bond are an epoxide or an aimulene-like structure. The possible products of this ozonolysis reaction are oxygen bridging over 6-6 bond C60O(C2v) as an epoxide-like isomer and bridging over 5-6 bond C60O(Cs) as an epoxide-like isomer. The sixteen isomers of C70O have been studied with respect to the same reaction mechanism. The most possible product in this ozonolysis reaction is the oxygen bridging across in the upper part (6-6 bond in C70O-2 or C70O-4) as an epoxide-like structure. The other possible product is C70O-8 (annulene-like structure), in which oxygen bridges across an between equatorial C-C bond in C70(D5h).
The molecular dynamics and semiempirical method are used to describe the motion of filllerene derivatives C60O and C70O at room temperature (300 K). This calculation results is more reliable than other calculation method.
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