Crystal structure of bis(3-carboxy-1-methylpyridinium) octabromide

This is the authors' abstract. We don't add key points for this paper.

The crystal structure of the title salt, bis(3-carboxy-1-methylpyridinium) octabromide, 2C 7 H 8 NO 2 + ·Br 8 2− , consists of 3-carboxy-1-methylpyridinium ( N -methylnicotinic acid) cations, which are stacked between relatively rare [Br 8 ] 2– anions. The polybromide [Br 8 ] 2– anion has point group symmetry 1̄ and can be described as being composed of two [Br 3 ] − anions connected with a Br 2 molecule in a Z -shaped manner. Contacts between neighboring octabromide anions ensure the creation of pseudo-polymeric chains propagating along [111]. The organic cations are located between anionic chains and are connected to each other through O—H...O hydrogen bonds and to the [Br 8 ] 2– anions through π...Br interactions that induce the creation of a supramolecular tri-periodic network. In addition, the presence of weak C—H...Br contacts leads to the creation of layers, which align parallel to (112̄).