金属离子与腺嘌呤异构体复合物的稳定性

在B3LYP/6-311++G<'**>//6-31+G<'*>基组水平上,结合PCM模型系统优化了气相和液相环境中14种腺嘌呤异构体与4种金属离子(Na<'+>,K<'+>,Mg<'2+>,ca<'2+>)形成的132个稳定复合物的结构.通过能量对比,得出了这些复合物在气液两相中的稳定性顺序及每种异构体与金属离子的最...

Stability of the Complexes Combined by Metal Ions and Adenine Base Isomers

132 stable complexes formed by metal ions(Na+，K+，Ca2+，Mg2+) and fourteen stable adenine tautomers in gas and aqueous phases were optimized at the B3LYP/6-311++G**//6-31+G* level in combination with the PCM models. By comparison, the stabilization ordering of all these stable complexes in aqueous phase is first obtained and the optimal binding site for a metal ion in a specific adenine tautomer is identified. Meanwhile, the differences of the ordering in the two different phases are analyzed systematically. Results indicate that it is solvent effect to induce different solute-solvent interaction and, as a result, lead to the stabilization ordering change from that in gas phase. It is the different metal ion effect to result in the different ordering of relative stability of a complex formed by different metal ion and identical adenine tautomer. For these changes, this article makes detailed analysis based on gas-phase binding energies (EBE) and aqueous phase polarized solute-solvent energies (Epol).