Exceptions to the rule: new hydrogen-bonded networks from an old reliableElectronic supplementary information (ESI) available: Experimental details regarding the syntheses, crystallographic information files (CIFs) and powder X-ray diffraction data for all reported compounds are provided. See DOI: 10.1039/c0ce00621a

The syntheses and crystal structures of lamellar solids constructed from 3,5-pyrazole dicarboxylic acid and amines are described. While in the past this combination has resulted in one, recurring layer motif, we report here that sterically demanding groups impose different hydrogen-bonding connectivity. The architecture adopted by ammonium HPzDCA salts can be related to the width of the ammonium substituents and the steric effects of strategically positioned groups.