Packing motifs in organic ammonium carboxylate salts: extension of the ring-stacking and ring-laddering concepts

Abstract

A detailed investigation of the structural motifs in organic ammonium (NH₄⁺) and primary ammonium (R–NH₃⁺) carboxylate salts using ring-stacking and ring-laddering concepts has been carried out. A survey of structures in the Cambridge Structural Database has shown that this ionic model is applicable to ammonium and primary ammonium carboxylate salts, and that the formation of 2-D nets, ladders or cubanes is affected by steric interactions between the substituents on the ions. Nine new crystal structures of ammonium and primary ammonium carboxylate salts are reported. The results from the CSD survey were used to successfully predict the formation of nets or ladders in the six new salts that have 1 : 1 stoichiometry.