Sarcosine sarcosinium chloride and sarcosine sarcosinium bromide

The crystal and molecular structures and vibrational spectra of sarcosine sarcosinium chloride (I) and sarcosine sarcosinium bromide (II) have been determined and are discussed. In the case of sarcosine sarcosinium bromide (II), an old publication exists, where the structure is reported, but the data given are less accurate and hydrogen positions have not been determined at all. Both salts are isotypic and crystallize in the orthorhombic system (space group Pca21), the asymmetric unit contains two formula units. The O⋯O distances in dimeric cations are equal to 2.469(2) Å and 2.463(2) Å in (I) and 2.453(3) Å and 2.464(3) Å in (II). The presence of these short hydrogen bonds is reflected in the infrared spectra. The vibrational spectra of sarcosinium chloride and sarcosinium bromide are shown for comparison.