H2O和OH在UO(100)表面吸附的密度泛函研究  

A Density Functional Theory Study on the Adsorption of H_2O and OH on UO(100) Surface

作　　者：郑金德[1] 陆春海[2] 陈文凯[1] 

机构地区：[1]福州大学化学系,福州350108 [2]中国工程物理研究院,绵阳621900

出　　处：《无机化学学报》2008年第9期1374-1380,共7页Chinese Journal of Inorganic Chemistry

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(No10676007);福建省高等学校新世纪优秀人才支持计划资助

摘　　要：运用密度泛函理论中的广义梯度近似(GGA)的PW91方法结合周期性平板模型,研究了H2O分子和OH在UO(100)表面上的吸附。通过对不同吸附位的吸附能和几何结构参数的计算和比较发现:水分子在UO(100)表面的吸附为化学吸附,水分子平面与UO(100)表面夹角为15°的吸附构型最稳定,吸附能最大,近89kJ.mol-1。对H2O吸附前后的态密度分析可知,H2O通过其O原子的p轨道与底物U原子的d轨道作用。本文还进一步探讨H2O在UO(100)表面的解离机理。The adsorption of H2O molecule and OH on UO（100） surface has been studied with periodic slab model by PW91 approach of GGA within the framework of density functional theory （DFT）. The results of geometry optimization indicate that the adsorption of H2O on UO（100） surface was chemical. The most stable structure of adsorption is that H2O aslant adsorbed with the tilt angle is about 15°, and the corresponding adsorption energy is predicted to be 89 kJ·mol^-1. From the calculated results of density of states of H2O before and after H2O adsorption on UO（100） surface, a strong interaction was found between the H2O p orbital and uranium d orbital. Meanwhile, the possible decomposition mechanism of H2O over UO（100） surface was discussed.

关 键 词：密度泛函理论 水 吸附 一氧化铀(UO) 

分 类 号：O641.121[理学—物理化学] O614.62[理学—化学]