This project is designed based on the two theoretical parts about energy storage and molecular rotors, and an experimental part about fuel generation. The focus of the first part this research was on the geometry and molecular orbital studies of group-III oxide nanocapsules including boron oxide, aluminum oxide, gallium oxide and indium oxide via density functional theory (DFT). The calculated electronic structure and simulated scanning tunneling microscopy (STM) images predicted that boron oxide and aluminum oxide have more propensities to form endohedral complexes; while, gallium oxide and indium oxide have more tendencies to construct exohedral complexes. Then, the capability of boron oxide nanocapsules to store noble gases (He, Ne and Ar), H2, N2, CO, CO2, NH3, CH4 and Cl2 on the outer surface and inside of the cage was investigated; and the stability sequences of endohedral complexes were compared to the reported results for C60. It is expected that these compounds are a good potential candidate for gas storage. In the following, a study on the electronic structure and water adsorption reactivity of active sites of alumina nanotube was presented. It seems that the opened end of nanotube is more reactive than the closed end and the center of nanotube. The second part of this research provides an information about thenconformational stability and rotational energy barrier of C60 dimers and N,N’-dibenzylideneethylenediamine derivatives. Depending on substitution, the calculated rotational energy barrier for HC60–C60R and RC60–C60R dimers is less than 7.3 and more than 10 kcal/mol, respectively (R = hydrogen, methyl, ethyl, i-propyl, t-butyl and trimethylsilyl). In the following, the effect of β-trimethylsilyl substituent on the stability, resonance structures and hyperconjugative interactions of a series of cyclic and acyclic β-silyl carbocations with molecular formula of RR′C+–CH2Si(Me)3 in the gas phase and in solution were considered. It is found that the contribution of carbenium ion and silylium ion to the resonance structures is depending on the type of R(R′) substituents. In the case of phenyl, phenylcyclopropyl, benzocyclobutyl, cyclopropenyl, and tropylium cation, the carbenium ion is the major contributor; while for alkyl, cycloalkyl and cyclopentadienyl substituents, the silylium ion is prefer. In the third part of this research, the influence of diketene acetone adduct on the reaction of methanol to gasoline conversion (MTG) over zeolite H-ZSM-5 catalyst was examined experimentally. Based on these results, addition of the of this additive could increase the non-aromatic and decrease the aromatic content of gasoline. Also, except for toluene, the contributions of other aromatic compounds are decreased.