Interaction in molecular crystals, 160 - Crystallization and structure determination of the different polyphenyl contact ion multiples [p-quaterphenyl(circle minus circle minus)][Na-circle plus(DME)(3)](2), [p-quaterphenyl(circle minus circle minus)(Na-circle plus(THF)(3))(2)] and [p-terphenyl(circle minus circle minus)Na(circle plus)(DME)(2)Na-circle plus(DME)](2)

The pi -hydrocarbons p-terphenyl and p-quaterphenyl are reduced to their dianions in aprotic solutions of different ethers at sodium metal mirrors. Single crystal structure determinations of the solvent-separated or solvens-shared contact ion multiples, [p-terphenyl(--)Na(+)(DME)(2)Na+DME](2), [p-quaterphenyl(--)][Na+(DME)(3)](2) and [p-quaterphenyl(--)(Na+(THF)(3))(2)], prove the essential cation solvation by the chelating dimethoxyethane (DME) versus the bulky tetrahydrofuran (THF) ligands: The solution network of equilibria between solvent separated and solvent shared ion aggregates can be considerably and transparently modified by the ether solvent selected. In addition, the structures of the monomeric sodium salts reveal partly novel details of metal cation coordination by contacts Na+ . . .O as well as Na+. . .C-pi such as in the dimeric sodium salt of p-terphenyl dianion, [(DME)(2)Na+(terphenyl(--))(Na+DME)(terphenyl(--))Na+(DME)(2)].