Molecular Structure Of Metal Hydrides, Molecular Reaction Dynamics, And Of Ni <sub> 4 </ Sub> Clusters Of Molecular Structure

Density functional (B3LYP/SDD and B3LYP/6-311G*) method with relativistic effective core potential (RECP) have been used to optimize the microstructure of ZrCo, ZrH, CoH, UH, Ni2, AlNi, UH2, HZrCo and Ni3, and to calculate their energy, potential energy functions, as well as their force constants and spectroscopic data. The hydrogenating reactions systems for ZrCo, Zr, Co have been studied based on RECP. A model for the theoretical investigation of metallic hydrides has been put forwarded by author. The atomic and molecular reaction dynamic processes for the collision of H+ZrCo and Co+ZrH systems have been studied based on the present potential energy function of HZrCo and Monte-Carlo puasi-classical trajectory approach. Based on the analysis of the Jahn-Teller effect, vibronic interaction and the resolution of group representations, the possible geometrical configurations of Ni4 have been derived for the first time, the results are in good agreement with the calculation esults.Firstly, the reasonable dissociative limits for the diatomic molecules of ZrCo, ZrH, CoH, UH, Ni2 and AlNi have been derived based on the Atomic and Molecular Reactive Statics(AMRS) and the resolution of group representations. The ground electronic states, which are X2?, X3?, X4? and X3?u respectively for these molecules, have also been optimized based on the RECP method. The Murrell-Sorbie potential energy functions for the diatomic molecules have been obtained according to the ab inilio data through the least square fitting method. The spectroscopic data, force constants have been derived from the potential energy functions.Secondly, the reasonable dissociative limits for the tri-atomic molecules UH2. HZrCo, Ni3 and AlNi2 have been derived based on the Atomic and Molecular Reactive Statics(AMRS) and the resolution of group representations. The ground electronic states, which are X3A2, X5A2, X5A1 and X2B2 respectively for these molecules, have also been optimized based on the RECP method. The analytic potential energy functions for ground states of ZrCoH, UH2 and Ni3 molecules havebeen derived by many-boy expansion method using their equilibrium geometry structure parameters, dissociation energy and force constants. These potential energy functions, which show the structure characteristics of the molecules exactly, can be regarded as foundation for molecular reaction dynamic processes investigation.Based on the analysis of the Jahn-Teller effect, vibronic interaction and the resolution of group representations, the possible geometrical configurations of Ni4 have been derived for the first time. The Gaussian-98 program has been used to optimize the geometrical configurations of Ni4 based on B3LYP/6-311G method. It is found that there are at least six different stable geometrical configurations for Ni4. The results show that the multiplicity of 2S+1=7 for cluster Ni4 is the most stable state among the eight geometry configurations. The derived configurations are fair in agreement with the calculated results. It is means that the Jahn-Teller effect is very important in the geometry distortion of the A4h and Td configuration for Ni4.Then, the atomic and molecular reaction dynamic processes for the collisions of H+ZrCo(v=0,j/=0) and Co+ZrH(v=0,j=0) systems have been studied based on the present potential energy function of ZrCoH by Monte-Carlo puasi-classical trajectory approach. The results show that both H+CoH(v=0,j=0) and Co+ZrH(v=0.j=0) have no energy threshold. The results also show that the reaction section for H+ZrCo(v=0.j=0) decrease with the initial energy increasing. The molecular reaction dynamic processes for the collisions are mainly elastic scattering and non-reaction when the initial energy is over 200kJ/mol. The mechanism for the disproportion phenomena in the hydrating-dehydrating of the ZrCo alloy has been discussed.In the last section of the paper, a model for the theoretical investigation of metallic hydrides has been built for the first time by the author. Density functional (B3LYP/SDD) Method with Re...