Advertisement

Intermolecular Interactions in Li+-glyme and Li+-glyme–TFSA Complexes: Relationship with Physicochemical Properties of [Li(glyme)][TFSA] Ionic Liquids

Authors

  • Dr. Seiji Tsuzuki,

    Corresponding author
    1. Research Initiative of Computational Sciences (RICS), Nanosystem Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568 (Japan), Fax: (+81) 29-851-5426
    • Research Initiative of Computational Sciences (RICS), Nanosystem Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568 (Japan), Fax: (+81) 29-851-5426

    Search for more papers by this author
  • Wataru Shinoda,

    1. Research Initiative of Computational Sciences (RICS), Nanosystem Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568 (Japan), Fax: (+81) 29-851-5426
    Search for more papers by this author
  • Dr. Shiro Seki,

    1. Materials Science Research Laboratory, Central Research Institute of Electric Power Industry (CRIEPI), 2-11-1 Iwado-kita, Komae, Tokyo 201-8511 (Japan)
    Search for more papers by this author
  • Prof. Yasuhiro Umebayashi,

    1. Graduate School of Science and Technology, Niigata University 8050, Ikarashi, 2-no-cho, Nishi-ku, Niigata City, 950-2181 (Japan)
    Search for more papers by this author
  • Dr. Kazuki Yoshida,

    1. Department of Chemistry and Biotechnology, Yokohama National University, 79-5 Tokiwadai, Hodogaya-ku, Yokohama 240-8501 (Japan)
    Search for more papers by this author
  • Prof. Kaoru Dokko,

    1. Department of Chemistry and Biotechnology, Yokohama National University, 79-5 Tokiwadai, Hodogaya-ku, Yokohama 240-8501 (Japan)
    Search for more papers by this author
  • Prof. Masayoshi Watanabe

    1. Department of Chemistry and Biotechnology, Yokohama National University, 79-5 Tokiwadai, Hodogaya-ku, Yokohama 240-8501 (Japan)
    Search for more papers by this author

Abstract

The stabilization energies (ΔEform) calculated for the formation of the Li+ complexes with mono-, di- tri- and tetra-glyme (G1, G2, G3 and G4) at the MP2/6-311G** level were −61.0, −79.5, −95.6 and −107.7 kcal mol−1, respectively. The electrostatic and induction interactions are the major sources of the attraction in the complexes. Although the ΔEform increases by the increase of the number of the O⋅⋅⋅Li contact, the ΔEform per oxygen atom decreases. The negative charge on the oxygen atom that has contact with the Li+ weakens the attractive electrostatic and induction interactions of other oxygen atoms with the Li+. The binding energies calculated for the [Li(glyme)]+ complexes with TFSA anion (glyme=G1, G2, G3, and G4) were −106.5, −93.7, −82.8, and −70.0 kcal mol−1, respectively. The binding energies for the complexes are significantly smaller than that for the Li+ with the TFSA anion. The binding energy decreases by the increase of the glyme chain length. The weak attraction between the [Li(glyme)]+ complex (glyme=G3 and G4) and TFSA anion is one of the causes of the fast diffusion of the [Li(glyme)]+ complex in the mixture of the glyme and the Li salt in spite of the large size of the [Li(glyme)]+ complex. The HOMO energy level of glyme in the [Li(glyme)]+ complex is significantly lower than that of isolated glyme, which shows that the interaction of the Li+ with the oxygen atoms of glyme increases the oxidative stability of the glyme.

Ancillary