Methylammonium hydrogen succinate monohydrate

Two recent studies show that this conclusion does not apply to very short hydrogen bonds. In methylammonium hydrogen succinate monohydrate, three normal hydrogen bonds, with O—H between 1.72 and 1.86 A exist, while a very... 

C. Flensburg, S. Larsen and R. F. Stewart, Experimental density study of methylammonium hydrogen succinate monohydrate. A salt with a very short O H- O hydrogen bond, J. Phys. Chem. 99, 10130-10141 (1995). 

O- -H bonds in the anion, the negative region of the Laplacian is not shared by the VSCCs of either of the 0-atoms. Similar situations are found for symmetric intermolecular O- H O HBs realized in the crystal structures of methylam-monium hydrogen succinate monohydrate [89] and methylammonium hydrogen maleate [90] considerable covalent signal (V p cp < 0) for the O -H interactions, without shared VSCCs with the 0-atoms. 

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