Escitalopram oxalate: co-existence of oxalate dianions and oxalic acid mol­ecules in the same crystal

The title compound {systematic name: (+)-(S)-3-[5-cyano-2-(4-fluoro­phen­yl)-1,3-dihydro­isobenzofuran-2­yl]­propan­amin­ium oxalate oxalic acid 0.325-hydrate}, 2C₂₀H₂₂FN₂O⁺·C₂O₄²⁻·C₂H₂O₄·0.325H₂O, is a mol­ecular salt of the N-protonated escitalopram cation. As well as charge-balancing oxalate dianions, neutral mol­ecules of oxalic acid are present. The component species inter­act by way of N—H...O and short O—H...O hydrogen bonds, resulting in supra­molecular chains.