1,1,3,3-Tetramethylguanidinium dihydrogenorthophosphate

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