1,1,3,3-Tetramethylguanidinium dihydrogenorthophosphate

In the title compound, C5H14N3+. H2PO4-, the cation has a central guanidinium fragment with a planar geometry, as expected for a central Csp(2) atom with a small charge delocalization along the three C-N bonds. The crystal packing is governed by hydrogen bonds so that the phosphate anions are linked head to tail, forming chains running parallel to the c direction. These chains in turn are interconnected by hydrogen bonds to intermediate tetramethylguanidinium cations forming hydrogen-bonded molecular layers stacked parallel to the bc crystal planes.