| The density functional theory based on the methods of general relativity,respectively studied using DMol3 software package in GGA-PBE method: Calculation of the two parts of the content. Hope this paper can help researchers to better study the hydrogen storage materials. The work and conclusions in this paper are as follows:（1）Density functional theory are carried out to calculate the ground-state structures and electronic properties of Cu2X（X=Sc-Zn） and Cu2X-nH（n=1-6） clusters.It is found that the dissociation adsorption of H2 molecules of Cu2 Ti has obvious advantages over the other mixed clusters. Variations of adsorption energies of Cu2XnH（n=1-6） are almost opposite to the energy gaps of Cu2X-（n-1）H（n=1-6）, which is especially evident in Cu and Zn. Odd-even variations of the distribution of d electrons near the Fermi energy in Cu3-nH and Cu2Zn-nH are opposite, which are strongly correlated to the number of H atoms.（2）The adsorption and dissociation of molecular hydrogen on Cu12X（X=Sc-Zn）clusters are investigated by using the method of density functional theory. The result shows that the ground state structures of Cu12 V, Cu12 Cr, Cu12 Mn and Cu12 Fe are the close packed Ih structure with center substitution, the Cu12 Co, Cu12 Ni, and Cu12 Zn clusters are all for loose C2 structure and similar to those of Cu13 clusters. Based on the Ih structure, the adsorption characteristics of H2 on Cu12X（X=VCo, Cu） were discussed, physisorption a H2 molecule, the mixed clusters have advantages over pure Cu13. About chemical adsorption, the Cu12 Mn and Cu12 Fe, as well as pure Cu13 clusters can produce chemisorption. And the chemical adsorption energy of Cu13H2 is the largest. For the ground state structure after the adsorption of hydrogen molecules,whether it is physical adsorption or chemical adsorption, its ground state structure are composed by the most stable structures of Cu12 X clusters and one H2 or two H atoms. |
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