A Study On The Aromaticity And Kinetic Stability Of All Possible Fullerene C₂₄ Isomer

The study on the aromaticity and kinetic stability of classical fullerenes and non-classical fullerenes is a topic of research in fullerene chemistry. In this study, the aromaticity of all the possible isomers of C24 and its heterofullerene isomers has been examined by the topological resonance energy(TRE) and percentage topological resonance energy(%TRE) methods. Their kinetic stability has been examined by the bond resonance energy(BRE) method.The main points of this thesis are outlined as follows:In chapter 1 the origins and development of concepts related to aromaticity are presented and the concepts of fullerenes and heterofulleres are introduced. Several conventional indices of aromaticity, including geometric, energetic, and magnetic indices were introduced and compared. The methods for determining kinetic stability of fullerenes are introduced. Finally, the research significance of this paper is presented.In chapter 2 a systematic investigation of the aromaticity of heterofullerene isomers of C24-2nBnNn(n = 3 or 6) and C12N12 formed from the initial C24 fullerene with D6 symmetry is performed using the TRE method. The relationship between the aromaticity of these isomers and the sites where boron or nitrogen atoms dope at the C24(D6) cage has been discussed. The results we obtained using the TRE method were compared with the nucleus independent chemical shift NICS(0) values at the cage center which were obtained by others. The local aromaticity have been studied by the means of the BRE method.In chapter 3 a systematic investigation on the aromaticity of the heterofullerene isomers of [4,6]-C12X12(X=B,N) formed from the initial C24 fullerene with Oh symmetry is performed using the TRE method. The kinetic stability are studied usingthe BRE method. The effects of the amount and the arrangement of nitrogen and boron atoms on the aromaticity of these molecules is analyzed. The local aromaticities have been studied by the means of the BRE method.In chapter 4 the aromaticity of 173 kinds of classical and nonclassical C24 fullerene isomers and their anions using the TRE and the %TRE methods. The local aromaticity of the individual rings was studied using the BRE method. The results we obtained using the TRE and %TRE methods were compared with the nucleus independent chemical shift NICS(0) values at the cage center which were obtained by others. The local aromaticity is studied using the BRE method. We predicted the kinetic stability of these isomers using the Min BRE method.In chapter 5 a systematic investigation on the aromaticity of the heterofullerene isomers of C22 BN, formed from the initial C24 fullerene with Oh symmetry is performed using the TRE method. The relationship between the aromaticity of these isomers and the sites where boron or nitrogen atoms dope at the C24(Oh) cage has been examined. The kinetic stability of these isomers was predicted by the using of the Min BRE method.