Theoretical studies on the interactions of cations with diazine
- 化学化工－已发表论文 
Density functional theory and MP2 calculations have been used to determine the geometries, stabilities, binding energies, and dissociative properties of cation-diazine complexes Mn+-C4H4N2 (Mn+ = Li+, B+, Al+, Be2+, Mg2+, Ca2+). The calculated results indicate that most complexes are stable except the pi complexes of Ca2+-pyridazine, Ca2+-pyrazine, Al+-pyrimidine and Al+-pyrimidine. The a complexes are generally much more stable than their pi counterparts. Among the pi complexes, the cation-pyrazine pi complexes have slightly higher stability. The nature of the ion-molecule interactions has been discussed by the natural bond orbital analysis and frontier molecular orbital interactions. In these sigma complexes, there is stronger covalent interaction between B+. and diazine. In the selected pi complexes, B+ and Be2+ have stronger covalent interaction with diazine, while the other cations mainly have electrostatic interaction with diazine.