Crystal structure of a (carb­oxy­meth­yl)tri­ethyl­aza­nium bromide–2-(tri­ethyl­aza­n­ium­yl)acetate (1/1) hydrogen-bonded dimer

The title compound, C(8)H(18)NO(2) (+)·Br(−)·C(8)H(17)NO(2), crystallizes as the bromide salt of a 50:50 mixture of (tri­ethyl­azaniumyl)­carb­oxy­lic acid and the zwitterionic (tri­ethyl­azaniumyl)­carboxyl­ate. The two organic entities are linked by a half-occupied bridging carb­oxy­lic acid hydrogen atom that is hydrogen-bonded to the carboxyl­ate group of the second mol­ecule. The tetra­lkyl­ammonium group adopts a nearly perfect tetra­hedral shape around the nitro­gen atom with bond lengths that agree with known values. The carb­oxy­lic acid/carboxyl­ate group is oriented anti to one of the ethyl groups on the ammonium group, and the carbonyl oxygen atom is engaged in intra­molecular C—H⋯O hydrogen bonds.