Potassium Tartronate and Ammonium Tartronate

Potassium tartronate (potassium hydroxypropanedioate, 2K⁺.C₃H₂O₅^2-), (I), crystallizes in the monoclinic P2₁/n space group, with Z = 4, and ammonium tartronate (ammonium hydroxypropanedioate, 2NH₄⁺.C₃H₂O₅^2-), (II), is orthorhombic, Pna2₁, Z = 4. There are two symmetry-independent cations in both (I) and (II). The coordination number of the K⁺ ion in (I) is seven, and the number of hydrogen bonds around the NH₄⁺ ion in (II) is four. This difference arises from the fact that the hydrogen bonding governs the number of O atoms around NH₄⁺ in (II), in contrast to the electrostatic interactions in (I).

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