镧系金属一氢化物有效芯势研究  

Effective core potentials study on lanthanide monohydrides

作　　者：龙兴贵[1] 赵鹏骥[1] 彭述明[1] 罗顺忠[1] 杨茂年[1] 田安民[2] 

机构地区：[1]中国工程物理研究院核物理与化学研究所,四川绵阳621900 [2]四川大学化学学院,四川成都610064

出　　处：《化学研究与应用》2002年第3期258-260,共3页Chemical Research and Application

摘　　要：采用Cundari和Stevens等推导的有效芯势对镧系金属一氢化物进行了理论计算 ,以探讨镧系金属元素与氢的相互作用。结果表明所有镧系金属一氢化物基态时理论上是稳定的 ,最稳定的是SmH ,最不稳定的是DyH ;键长计算结果显示 ,基态时镧系金属一氢化物有镧系收缩现象发生 ;红外振动频率理论计算值与实验结果一致 ;成键轨道中 ,金属原子轨道的贡献主要是s轨道和d轨道 :从CeH至ErH(GdH例外 )随着外层电子的增加s轨道成分逐渐增大d轨道成分逐渐减小 ;从TmH到LuH(包括GdH) ,成键轨道中金属原子轨道的贡献主要是d轨道 ,约为 90 % ;绝大多数镧系金属一氢化物的成键轨道中金属原子轨道f成分小于 1%。Optimized bond length,total energy,IR vibrating frequencies,thermodynamic parameters,and NBO analysis of lanthanide monohydrides are systemically studied through B3LYP/CEP-121g level calculation with gaussian 98 program.Results of total energy analysis and thermodynamic analysis revealed that all of ground state configurations of these monohydrides are theoretically stable.The most stable monohydride is SmH,and the unstable is DyH.Calculated IR frequency of YbH is close to the experimental result,and it revealed that the calculated vibrating frequencies of lanthanide monohydrides are believable.NBO results indicated that contribution of metal atom in bond orbit of monohydride is mainly by s component and d component,and contribution of f component for most MH is less than 1%.

关 键 词：有效芯势 镧系金属 氢化物 B3LYP 氢 相互作用 红外光谱 构型 热力学 

分 类 号：O614.33[理学—无机化学] O641.121[理学—化学]