摘要
用ＣＮＤＯ／２方法经ＳＣＦ计算获得了钌（Ⅱ）联吡啶配合物ｃｉｓ－［ＲｕⅡ（ｂｐｙ）２（Ｌ）２］的电子结构（其中ｂｐｙ＝２，２′－二联吡啶；Ｌ＝Ｃｌ－，ＮＣＳ－，ＣＮ－，ＮＨ３，ＮＣＣＨ３）．计算结果表明，这些钌（Ⅱ）联吡啶配合物的ＬＵＭＯ均定域于配体ｂｐｙ的最低能π轨道，而其ＨＯＭＯ均定域于中心钌（Ⅱ）原子的ｄπ轨道．随着配体Ｌ的σ电子给予能力的增强，对应配合物的ＨＯＭＯ能级相应增大，ＬＵＭＯ能级亦有所增大，两者之差值则降低．这些钌（Ⅱ）联吡啶配合物的ＨＯＭＯ和ＬＵＭＯ能级变化趋势分别与相应的第一氧化和第一还原电势变化趋势相同，并且ＨＯＭＯ和ＬＵＭＯ能级与其光谱最低吸收能和第一氧化还原电势呈现出很好的线性相关性．计算结果与实验数据相吻合．
The electronic structures of ruthenium(II) complexes cis-[RuⅡ(bpy)2(L)2] have been obtained by CNDO/2 SCF-MO calculation, where bpy=2,2′-bipyridine and L=Cl-,NCS-,CN-,NH3,NCCH3. Calculation results show that the HOMO and LUMO of cis-[RuⅡ(bpy)2(L)2] are located respectively in the dπ(Ru) and the lowest π*(bpy) orbitals. As σ-donating ability of L ligand increases, HOMO energies of cis-[RuⅡ(bpy)2(L)2] increase, simultaneously corresponding LUMO energies somewhat increase, and their differences decrease. The HOMO and LUMO energies possess the same variation tendency as the first oxidation and first reduction potentials respectively and meanwhile show good linear correlations with the redox potentials and the lowest absorption energies respectively. Calculations are in agreement with the experimental data.
出处
《分子科学学报》
CAS
CSCD
1998年第2期38-41,共4页
Journal of Molecular Science
基金
江苏省科委自然科学基金
