<p>To investigate the role of stereochemistry in supramolecular assembly, we constructed a supramolecular system incorporating crown ether derivatives bearing chiral centers. Supramolecular systems were constructed in [Ni(dmit)₂]⁻ salts by 4-aminopyridinium (4-ApyH⁺) and chiral crown ether isomers: <i>trans-anti-trans</i>-dicyclohexano[18]crown-6 (<i>tat</i>-DCH18C6) or <i>trans-syn-trans</i>-dicyclohexano[18]crown-6 (<i>tst</i>-DCH18C6). Racemic crystals of (4-ApyH⁺)(<i>tat</i>-DCH18C6)[Ni(dmit)₂]⁻ (<b>1</b>) and (4-ApyH⁺)(<i>tst</i>-DCH18C6)[Ni(dmit)₂]⁻ (<b>2</b>) have one-dimensional (1D) supramolecular chains via N–H···O hydrogen bonds between 4-ApyH⁺ and crown ether derivatives, but the stereochemistry of the crown ether derivatives affects the geometric structure of the supramolecular 1D chain. Crystal <b>1</b> adopted space group <i>Pnc</i>2, with the supramolecular cations arranged in a zigzag 1D manner. Crystal <b>2</b> had space group <i>P</i>-1, with a linear 1D chain of supramolecular cation. Disorder was observed in the 4-ApyH⁺ cations in both structures, suggesting the presence of molecular space allowing dynamic behaviour. Temperature dependence of the molar magnetic susceptibility in both crystals showed antiferromagnetic interaction between [Ni(dmit)₂]⁻ anions. The subtle stereochemical differences in the crown ether suggest controllability of the supramolecular assembly pattern, the space available for the molecular motion of the cation, and the strength of magnetic interactions mediated by the arrangement of the magnetic anion. This provides a foundation for designing novel functional molecular materials with coupling between dynamic properties and electronic functions.</p> Graphical abstract <p>Chiral crown ether stereochemistry directs supramolecular assembly, resulting in zigzag and linear cation chains. This control regulates cationic dynamic space and modulates antiferromagnetic interactions, expecting a link between structure, dynamics, and electronic functions.</p>