Аннотация:3-Hydroxypiperidinium pentaiodide was synthesized by a facile reaction in concentrated aqueous HI. Its crystal structure comprises 3-hydroxypiperidinium cations and pentaiodide anions, the latter having geometry of cis -shaped chains composed of I 2 and I 3 - building units. The analysis of interatomic distances, Raman spectroscopy data, and results of DFT calculations, including non-covalent interaction analysis, showed that the title compound exhibits a complex pattern of covalent and non-covalent interactions. Those include I–I covalent bonds and I···I halogen bonds within the I 5 - anion as well as (N)H···I and (O)H···I hydrogen bonds and even weaker (C)H···I van-der-Waals interactions between the cations and anions