物理化学学报 >> 2009, Vol. 25 >> Issue (04): 655-660.doi: 10.3866/PKU.WHXB20090419

研究论文 上一篇    下一篇

气相和水溶液中铀酰配合物UO2L 2-n*an (L=F-, CO2-3, NO-3; n=0-6, a=1, 2)的结构和振动光谱

辜家芳 陆春海 陈文凯 许莹 郑金德   

  1. 福州大学化学系, 福州 350108; 表面物理与化学国家重点实验室, 四川 绵阳 621907; 中国科学院福建物质结构研究所, 福州 350002
  • 收稿日期:2008-11-07 修回日期:2008-12-19 发布日期:2009-03-31
  • 通讯作者: 陈文凯 E-mail:qc2008@fzu.edu.cn

Structures and Vibrational Frequencies of Gas Phase and Solvated Uranyl Complexes UO2L 2-n*an (L=F-, CO2-3, NO-3; n=0-6, a=1, 2)

 GU Jia-Fang, LU Chun-Hai, CHEN Wen-Kai, XU Ying, ZHENG Jin-De   

  1. Department of Chemistry, Fuzhou University, Fuzhou 350108, P. R. China; State Key Laboratory for Surface Physics and Chemistry, Mianyang 621907, Sichuan Province, P. R. China; Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002, P. R. China
  • Received:2008-11-07 Revised:2008-12-19 Published:2009-03-31
  • Contact: CHEN Wen-Kai E-mail:qc2008@fzu.edu.cn

摘要:

通过对铀采用相对赝势基组, 其它原子使用6-31+G(d)基组, 应用密度泛函理论(DFT)以及B3LYP方法对UO2+2离子与F-、CO2-3和NO-3的各配位结构进行优化和频率计算. 计算考虑了气相和水溶剂化两种状态, 其中溶剂化模型采用连续导体介质理论模型(CPCM). 计算结果显示配体的配位数与O=U=O对称伸缩振动频率存在线性关系. 配体在气相和水溶液中存在的关系基本符合通式: νs=-Agasn+983和νs=-Aaqn+821(Agas 和Aaq为常数, 表示每增加一个配体振动频率的变化值; n为配体配位数). 其中F-对应Agas=53 cm-1, Aaq=11 cm-1; CO2-3对应Agas=85 cm-1, Aaq=19 cm-1; NO-3对应Agas=48 cm-1, Aaq=-10 cm-1. 并且Aaq值与实验值一致.

关键词: 铀酰离子, 密度泛函理论, 相对论赝势, 溶剂化, 振动频率

Abstract:

The geometries and IR frequencies of uranyl complexes were calculated by B3LYP method in density
functional theory (DFT) using the relative effective core potential (RECP) on uraniumand 6-31+G(d) basis set on other elements. Both gaseous and aqueous phases were considered and conductor-like polarized continuum model(CPCM) was used to consider the solvation effect of water. Ligands investigated in the present paper were F-, CO2-3, and NO-3. A linear correlation between the frequency of the O=U=O symmetrical stretching vibration and the number (n) of ligands was established for the above-mentioned ligands according to the following two equations: νs=-Agasn+983 and νs=-Aaqn+821, where Agas and Aaq are characteristic coefficients that represent the shift in vibrational frequency for the addition of each ligand to the uranyl center. Results obtained for F- fit the equations with Agas=53 cm-1 and Aaq=11 cm-1; CO2-3 with Agas=85 cm-1 and Aaq=19 cm-1; NO-3 with Agas=48 cm-1 and Aaq=-10 cm-1. The value of Aaq was found to correspond to the experimental results.

Key words: Uranyl cation, Density functional theory, Relative effective core potential, Solution effect, Vibration frequency

MSC2000: 

  • O641