Compound 1 is a onedimensional coordination polymer containing double chains incorporating pairs of edgesharing NdO9 polyhedra linked by glutarate dianions. <...> A network of O—H O and O—H Cl hydrogen bonds helps to consolidate the structure. <...> Its glutarate ion adopts an extended conformation, whereas its hydrogen glutarate ion takes on a twisted conformation. <...> INTRODUCTION Glutaric acid HO2C(CH2)3CO2H (H2glut or C5H8O4) has applications in polymer chemistry [ 1 ] and can form liquid crystals [ 2 ]. <...> In its doubly-deprotonated form (glu2–), it is a versatile bridging ligand with a flexible backbone and many coordination polymers have been reported in combination with both transition metal and rare-earth cations [ 3—8]. <...> Five drops of a 1 N NaOH solution was added to raise the pH of the glutaric acid solution. <...> The mixture was filtered and kept at room temperature for crystallization. <...> After 10 days, pink blocks of 1 were recovered in 43 % yield by filtration and rinsing with ethanol. <...> Eight drops of a 1 N NaOH solution was added to raise the pH of the glutaric acid solution. <...> The solutions were mixed and stirred for 1 h at room temperature. <...> The mixture was filtered and kept at room temperature for crystallization. <...> After 10 days, light green needles of 2 were recovered by vacuum filtration and rinsing with ethanol (yield = 48 %). <...> The IR spectra of 1 and 2 were recorded on a Perkin—Elmer FTIR 180 spectrophotometer using KBr pellets over the frequency range 4000—400 cm–1. <...> The water H atoms were located in difference maps and refined as riding atoms in their as-found relative positions. <...> The carboxylic acid H atom in 2 was located in a different map and its position freely was refined. <...> These assignments are consistent with the different bonding modes of the glutarate ion in the crystal structure of 1 (vide infra). <...> The C=O stretch in free glutaric acid occurs at 1699 cm–1. <...> A strong, very broad band centered around 3350 cm–1 in 1 corresponds to the O—H vibrations of hydrogen bonded water molecules and a cluster of weak, overlapped bands around 645 cm <...>