Molecular Structure and Dynamics of LiClO4 + 18-Crown-6 Macrocyclic Complexes in Dimethyl Carbonate at 25 C

摘要

The structure and mechanism of migration of electrolytes complexed by macrocycles in solvents of very low permittivity is a problem of continuing interest to researchers in fields as different as biology and electrochemistry. For instance, it is important to know whether in media mimicking biological membranes an electrolyte complexed by macrocycles such as valinomycin is still in the form of ion pairs. Similarly, it is relevant for electrochemists involved in the construction of secondary lithium batteries to find ways to ionize the electrolyte dissolved in the low-permittivity medium, to decrease the internal resistance of the battery. To answer as many of the above questions as possible with a model system, electrical conductivity, infrared spectra, and microwave dielectric spectra of the electrolyte LiC1O4 with the macrocycle 18C6 (18-crown-6) dissolved in the solvent DMC (dimethyl carbonate) have been reported here and compared (the conductances and dielectric data) to results reported previously for LiC1O4 alone in DMC. Lithium perchlorate, Reprints. (mjm)