Tsuzuki Seiji, Mandai Toshihiko, Suzuki Soma, Shinoda Wataru, Nakamura Takenobu, Morishita Tetsuya, Ueno Kazuhide, Seki Shiro, Umebayashi Yasuhiro, Dokko Kaoru, Watanabe Masayoshi
Research Center for Computational Design of Advanced Functional Materials (CD-FMat), National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568, Japan.
Phys Chem Chem Phys. 2017 Jul 19;19(28):18262-18272. doi: 10.1039/c7cp02779f.
The interactions of glymes with alkali or alkaline earth metal cations depend strongly on the metal cations. For example, the stabilization energies (E) calculated for the formation of cation-triglyme (G3) complexes with Li, Na, K, Mg, and Ca at the MP2/6-311G** level were -95.6, -66.4, -52.5, -255.0, and -185.0 kcal mol, respectively, and those for the cation-tetraglyme (G4) complexes were -107.7, -76.3, -60.9, -288.3 and -215.0 kcal mol, respectively. The electrostatic and induction interactions are the major source of the attraction in the complexes; the contribution of the induction interactions to the attraction is especially significant in the divalent cation-glyme complexes. The binding energies of the cation-G3 complexes with Li, Na, K, Mg, and Ca and the bis(trifluoromethylsulfonyl)amide anion ([TFSA]) were -83.9, -86.6, -80.0, -196.1, and -189.5 kcal mol, respectively, and they are larger than the binding energies of the corresponding cation-G4 complexes (-73.6, -75.0, -77.4, -172.1, and -177.2 kcal mol, respectively). The binding energies and conformational flexibility of the cation-glyme complexes also affect the melting points of equimolar mixtures of glyme and TFSA salts. Furthermore, the interactions of the metal cations with the oxygen atoms of glymes significantly decrease the HOMO energy levels of glymes. The HOMO energy levels of glymes in the cation-glyme-TFSA complexes are lower than those of isolated glymes, although they are higher than those of the cation-glyme complexes.
乙二醇二甲醚与碱金属或碱土金属阳离子的相互作用在很大程度上取决于金属阳离子。例如，在MP2/6 - 311G**水平下，计算得到的锂、钠、钾、镁和钙与三甘醇二甲醚（G3）形成阳离子 - 三甘醇二甲醚配合物的稳定能（E）分别为 -95.6、-66.4、-52.5、-255.0和 -185.0千卡/摩尔，而阳离子 - 四甘醇二甲醚（G4）配合物的稳定能分别为 -107.7、-76.3、-60.9、-288.3和 -215.0千卡/摩尔。静电和诱导相互作用是配合物中吸引力的主要来源；在二价阳离子 - 乙二醇二甲醚配合物中，诱导相互作用对吸引力的贡献尤为显著。锂、钠、钾、镁和钙的阳离子 - G3配合物与双（三氟甲基磺酰）亚胺阴离子（[TFSA]）的结合能分别为 -83.9、-86.6、-80.0、-196.1和 -189.5千卡/摩尔，且它们大于相应阳离子 - G4配合物的结合能（分别为 -73.6、-75.0、-77.4、-172.1和 -177.2千卡/摩尔）。阳离子 - 乙二醇二甲醚配合物的结合能和构象灵活性也会影响乙二醇二甲醚与TFSA盐等摩尔混合物的熔点。此外，金属阳离子与乙二醇二甲醚中氧原子的相互作用会显著降低乙二醇二甲醚的最高占据分子轨道（HOMO）能级。阳离子 - 乙二醇二甲醚 - TFSA配合物中乙二醇二甲醚 的HOMO能级低于孤立乙二醇二甲醚的HOMO能级，尽管它们高于阳离子 - 乙二醇二甲醚配合物的HOMO能级。
