Theoretical Study On Doped Carbon Clusters C_nBi^-(n=1-11) And C_nF₃^-(n=1-9)

The dissertation is devoted to the theoretical study on Bi-doped carbon clusters anions C_nBi^-(n=1-11) and F-doped carbon clusters anions C_nF₃^-(n=1-9).For C_nF₃^-(n=1-9) clusters,All kinds of possible models are explored employing B3LYP/6-311G^* combining Molecular Graphics and Molecular Mechanics.To ascertain the lowest-lying structures,the single point energies are calculated at the level B3LYP/6-311+G^*.For C_nBi^-(n=1-11) clusters,B3LYP method and counterfeit potential basis set,that is,Lanl2dz basis set for Bi atom and 6-31G^* basis set for C atoms,were used to optimize the models.Then the single point energies were calculated by larger basis set 6-311+G^* for carbon atoms to explore the ground-state structures.In the way of NBO calculation and the analysis of valence bond structures, we summarize the structural rules.And the parity alternation in the time-flight mass spectra is interpreted based on the compare of the Electron Affinities,the Energy Difference and the Incremental Binding Energies.Main results and conclusions could be summarized as follows:1.C_nBi^-(n=1-11) anions clustersWe ascertain the ground state of anions clusters C_nBi^-(n=1-11) through the theoretical computation.The lowest-lying structures of C_nBi^- are linear.The clusters with "even-n" are more stable than those with "odd-n".The odd/even alternation trend can be explained according to the Energy Differences,Incremental Binding Energies and the analysis of valence bond structures.The results of calculation are in good agreement with the experimental phenomena observed in mass spectrometric studies.2.C_nF₃^-(n=1-9) anions clustersThe stabilities of the C_nF₃^-(n=1-9) anions clusters exhibit obvious even/odd alternations.The lowest-lying structures are established by theoretical computation.We discuss its impact on the structure of the cluster.The clusters with "odd-n" are more stable than those with "even-n",which can be concluded from the Energy Differences, and the Incremental Binding Energies.The results of the calculations are in good agreement with experimental data.Knowledge acquired in this dissertation can provide helpful information for the synthesis of a variety of novel cluster-assembled materials.