Theoretical Investigation of Energy Storage in Atomic and Molecular Systems: Metastable Molecular Fuels.

摘要

Ion-pair species bound by the coulomb attraction between a stable positive and stable negative ion have been investigated theoretically as candidate high-energy fuels that could form the basis of new propulsion schemes. Theoretical results for H3O, Li3H, and H3F are presented along with specific impulse (Isp) predictions based on calculated energies. The ion-pair local minimum on the first excited potential surface of H3O is found to be unstable with respect to dissociation to H2 + H + O. The ion-pair state of H3F has a double degenerate imaginary frequency. These results support the general conclusion that ion-pair states based on the H3 cation will not be stable because back-charge transfer to H3.. lead to neutral H3, which is unstable with respect to H2 + H. The ion-pair state of Li3H is found to be a local minimum with, however, a very small barrier to conversion to the lower energy planar form. Even the lowest energy form of Li3H as an additive to hydrogen is predicted to provide a 16% improvement in Isp.