The 1:2:1 adduct of DABCO dication, hydrogen squarate and water molecules studied by X-ray diffraction and FTIR spectroscopy

► X-ray, FTIR of 1,4-diazoniumbicyclo[2.2.2]octane bis(hydrogen squarate) monohydrate. ► The hydrogen squarate anions form hydrogen-bonded α-chain. ► The chains are linked by water molecules into ribbons. ► DABCO dication interacts by NH⋅O trifurcated hydrogen bonds with HSQ− anion and water. ► Bands due to γCC vibrations of HSQ− interrupt the broad absorption in FTIR spectrum.