摘要
采用从头算方法研究了一系列超碱金属阳离子BM6+,CM5+,NM4+,OM3+和FM2+(M=Li,Na).在MP2/6-311+G(d)水平上优化了这些体系的几何结构,并对频率进行了分析.计算得到它们最稳定结构分别具有Oh,D3h,Td,D3h和D∞h对称性.中心原子电负性越高,与配体碱金属原子之间的键长越短,相互作用越强.在CCSD(T)/6-311+G(3d,f)理论水平下计算了阳离子体系的垂直电子亲和势(EEA,v),EEA,v值的范围在3.26～3.86 eV之间,都低于Cs原子的第一电离势(3.90 eV).
Superalkalies with low ionization potentials（IPs） can exhibit behaviors reminiscent of alkali metal atoms and hence can be considered as potential building block for assembling novel nanostructured materials.A series of cluster cations BM＋6,CM＋5,NM＋4,OM＋3,and FM＋2（M=Li,Na） are theoretically predicted using ab initio calculations.The global minimum energy structures of these species are obtained at the MP2/6-311＋G（d） level and possessing Oh,D3h,Td,D3h,and D∞h symmetries,respectively.The vertical electron affinities for these cations calculated at the CCSD（T）/6-311＋G（3d,f） level are lower than the IP=3.90 eV of Cs atom,thus they should be classified as superalkali cations.Moreover,the dependence of EEA,v values of these superalkali cations on the electronegativity of central atom and alkali atom ligand is discussed.
出处
《分子科学学报》
CAS
CSCD
北大核心
2010年第4期252-255,共4页
Journal of Molecular Science
基金
国家自然科学基金资助项目(20503010)
关键词
超原子
超碱金属
电负性
垂直电子亲和势
从头算
superatom
superalkalies
electronegativity
vertical electron affinities
ab initio
