Crystal structure, spectroscopic and thermal studies of anhydrous potassium 2,6-dihydroxybenzoate

The crystal structure, infrared spectrum and thermal stability of the potassium salt of 2,6-dihydroxybenzoic acid have been studied. The compound crystallizes in the monoclinic space group P21/n with a = 3.847(1) Å, b = 15.099(5) Å, c = 13.248(4) Å,  = 98.35(2)° and Z = 4. The compound of the general formula KL is a three-dimensional polymer, in which K ions are bridged by coordinated organic ligands by oxygen atoms of carboxylate and hydroxy groups. The anhydrous compound decomposes at 230°C. The IR spectrum of the potassium salt is discussed.