Computational studies of ion pairing. 10. Ion pairing between tetrabutylammonium ion and inorganic ions: a general motif confirmed.

Abstract

Until recently, little has been known about the nature of the factors governing the stereochemistry of the interactions between organic ions, even though such information should be directly relative to issues of molecular recognition and supermolecular self-assembly. The present study of the preferred structures of the ion pairs between tetrabutylammonium and 22 common inorganic ions, a continuation of previous studies in this series, brings to 93 the number of such species that have been examined in this way. In every one of these ion pairs, the minimum energy orientation of the cation relative to the anion is the same, reinforcing the conclusion that this structural motif is completely general. This is the first such pattern to be identified for the mode of association between organic cations and polar species in solution.