论文部分内容阅读
本文用CNDO/2方法从理论上探讨了碱金属离子Na~+,K~+和Ca~+与2,3-苯并-8,11,15-三甲基-18-冠-6(简称BC3-18C6)在溶液中发生的配位反应,计算了配位反应中CNDO总能量的变化,再现了量热法所得出的碱金属离子Na~+,K~+和Cs~+与BC3-18C6在溶液中生成配合物的稳定性次序:K~+>Na~+>Cs~+. 所计算的配位能和配合物的水化能表明,在水溶液中碱金属水合离子与冠醚配位,形成稳定的二水配位的碱金属离子冠醚配合物[M(BC3-18C6)(H_2O)_2]~+. 碱金属离子与冠醚中的氧形成的金属-氧键不如其水合物中的金属-氧键强.碱金属离子能与冠醚配位形成稳定的配合物主要是由于配体的大环效应和配合物的溶剂化作用.
In this paper, the CNDO / 2 method was used to theoretically investigate the effects of alkali metal ions Na ~ +, K ~ + and Ca ~ + with 2,3-benzo-8,11,15-trimethyl-18- BC3-18C6) in solution. The change of total energy of CNDO in coordination reaction was calculated. The results showed that the content of Na ~ +, K ~ +, Cs ~ + and BC3- The order of stability of 18C6 complex formed in solution is K ~ +> Na ~ +> Cs ~ +. The calculated coordination energies and the hydration energies of the complex show that the hydration energy of alkali metal hydrate and aqueous solution of crown ether (H 2 O 2) ~ +. The metal-oxygen bond formed between the alkali metal ions and the oxygen in the crown ether is not as good as that of the hydration of the alkali metal ion crown ether complex [M (BC 3-18C 6) The metal - oxygen bond is strong.The coordination of alkali metal ions with crown ether to form a stable complex is mainly due to the macrocyclic effect of the ligand and the solvation of the complex.