摘要
用密度泛函理论(DFT)研究了标题化合物的电子结构、电离能和稳定性。研究发现,体系的交错型(D4d)结构是稳定的,而重叠型(D4h)异构体则是过渡态。从垂直电离能的计算可知,Fe、Ru和Os的配合物对分子内的库仑排斥力而言是不稳定的,而Co、Rh和Ir的类似物则是稳定的。此外,计算结果表明,钠能作为抗衡离子来抵消分子内的库仑排斥力,使电子不会自发地离去,因为这样可以产生更稳定的结构,即[P4MP4Na]-,从而可以便于实验操作。另外,金属-配体裂解反应能的计算表明这些夹心型配合物都是热稳定的。
The equilibrium geometries,electron detachment energies and stabilities of the new type sandwich structures [P4MP4]^n-（M=Fe,Ru,Os,Co,Rh,and Ir;n=1 or 2） and [P4MP4Na]^-（M=Fe,Ru,Os） are predicted by the density functional theory.The calculations reveal that the n-complexes adopt the staggered D4d conformers as their stable structures,and the D4d structures belong to transition states.The computation of the vertical electron detachment energies of these complexes suggests that the Fe,Ru,and Os species are unstable in terms of intramolecular Coulomb repulsion,while the analogs of Co,Rh,and Ir are all stable.In addition,sodium can be used as counter ions to counteract the Coulomb repulsion,which can yield stabilization toward electron detachment and provide convenience for experiments.The calculated results also reveal that the sandwich structures are all stable thermodynamically,because the dissociations of [P4MP4]^n- and [P4MP4Na]^-into separated fragments are both endothermic reaction.
出处
《化学试剂》
CAS
CSCD
北大核心
2010年第7期593-599,共7页
Chemical Reagents
