气相和水溶液中铀酰配合物UO2Ln^2-n＊a(L=F^-,CO3^2-,NO3^-;n=0-6,a=1,2)的结构和振动光谱  

Structures and Vibrational Frequencies of Gas Phase and Solvated Uranyl Complexes UO_2L_n^(2-n*a)(L=F^-,CO_3^(2-),NO_3^-;n=0-6,a=1,2)

作　　者：辜家芳[1] 陆春海[2] 陈文凯[1] 许莹[3] 郑金德[1] 

机构地区：[1]福州大学化学系,福州350108 [2]表面物理与化学国家重点实验室,四川绵阳621907 [3]中国科学院福建物质结构研究所,福州350002

出　　处：《物理化学学报》2009年第4期655-660,共6页Acta Physico-Chimica Sinica

基　　金：国家自然科学基金委员会-中国工程物理研究院联合基金(10676007);福建省高等学校新世纪优秀人才支持计划(HX2006-103);国家重点实验室基金(9140C6601010804)资助项目

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UO22+离子与F-、CO23-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襒U襒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=53cm-1,Aaq=11cm-1;CO230-对应Agas=85cm-1,Aaq=19cm-1;NO-3对应Agas=48cm-1,Aaq=-10cm-1.并且Aaq值与实验值一致.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 uranium and 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-,CO230-,and NO3-. 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; CO230-with Agas=85 cm-1 and Aaq=19 cm-1; NO3-with Agas=48 cm-1 and Aaq=-10 cm-1. The value of Aaq was found to correspond to the experimental results.

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 

分 类 号：O641.4[理学—物理化学]