Structure of metaraminol hydrogen tartrate from synchrotron X-ray data and density functional theory calculations.

The crystal structure of the title salt, C9H14NO2 +·HC4H4O6 -, has been solved and refined using synchrotron X-ray powder diffraction data and optimized using density functional theory techniques. The crystal structure consists of alternating hydro-phobic and hydro-philic layers lying parallel to the ab plane. Hydrogen bonds link the cations and anions in the hydro-philic layers. The anions are linked by very strong charge-assisted O-H⋯O hydrogen bonds into chains propagating along the a-axis direction. Each H atom of the protonated N atom of the cation acts as a donor in at least one N-H⋯O hydrogen bond to an anion.