【摘要】 文章采用密度泛函理论(DFT)中的B3LYP方法,分别在LANL2DZ基组、CEP-121G基组及SDD基组下,优化团簇Yn(n=1-4)的几何结构。计算结果表明Y和Y+的基态分别是二重态和三重态;Y2和Y+2的基态分别是五重态和四重态;Y3和Y+3的基态分别是二重态和三重态,具有D3h对称性的等边三角形结构;Y4和Y+4的基态分别是三重态和二重态,具有C3v对称性的金字塔结构和Cs对称性的金字塔结构。计算得到团簇Yn的3种电离势,其中第一类电离势IPverI与实验结果吻合得较好,而用后2种基组计算所得结果与实验值误差约2%。更多还原

【Abstract】 The structure of neutral and cationic Y_n（n=1～4） clusters is studied within the framework of Kohn-Sam density functional theory （DFT） with the B3LYP method and with LANL2DZ basis set, CEP-121G basis set and SDD basis set respectively. The calculations show that the ground states of Y and Y^<sup>+are doublet and triplet respectively,that the ground states of Y_<sub>2 and Y^<sup>+₂ are quintuplet and quadruplet respectively,that the ground states of Y_<sub>3andY^<sup>+₃ are doublet and triplet of equilateral triangle structure with D_<sub>3hsymmetry respectively,and that the ground states of Y_<sub>4and Y^<sup>+₄ are triplet and doublet of pyramid structurewith C_<sub>3vsymmetry and C_ssymmetry respectively. The first type ionization potentials of the Y_n clusters are in good agreement with the available experiment data, and the errors between the calculations and the experimental data with CEP-121G basis set or SDD basis set are less than 2%. The other two kinds of calculated ionization potentials would be verified by other experiments henceforth.更多还原