organic compounds
The title compounds, C6H14NO2+.Br− and C8H18NO2+.Br−, each crystallize forming three-dimensional networks of Br−N+ contacts and Br−H—O hydrogen bonds. n-Butyl(carboxymethyl)dimethylammonium bromide has two molecules in the asymmetric unit. The orientation of the alkyl chain relative to the polar part of the molecule is different in the two compounds.