Iodides of sarcosine

► Crystals Sar·HI and 2Sar·HI are obtained and characterized structurally and by IR, Raman spectra. ► 2Sar·HI is a new salt with dimeric Sar⋯Sar+ cation and 2.496(4) Å O⋯O distance. ► Sar·HI (space group P21) is isotypic with Sar·HCl and Sar·HBr. ► 2Sar·HI (space group P21/c) is not isostructural with 2Sar·HCl and 2Sar·HBr (space group Pac21).