AbstractA one‐dimensional (1D) Ni(II) coordination polymer, {[Ni(oba)(1,3‐bix)(H2O)]⋅H2O}n (1), where H2oba=4,4′‐oxybis(benzoic acid) and 1,3‐bis(imidazol‐l‐yl‐methyl)benzene=1,3‐bix, was hydrothermally synthesized and characterized through IR spectroscopy, elemental and thermal analysis, single‐crystal X‐ray diffraction, and Hirshfeld surface analyses. X‐ray diffraction structural analysis has revealed that the oba and 1,3‐bix ligands connects the Ni(II) atoms to form a square‐wave 1D chain, which is further extended into 2D supramolecular layers through O−H⋅⋅⋅O hydrogen bonds and π⋅⋅⋅π stacking interactions. 1 shows intense luminescence in H2O and exhibits a selectivity and detection for Fe3+ ions through the fluorescence quenching effect at room temperature.