Hydrogen bonded NHO chains formed by chloranilic acid (CLA) with 4,4′-di-t-butyl-2,2′-bipyridyl (dtBBP) in the solid state

► We synthesized a novel molecular complex, dtBBP·CLA. ► We determined the crystal structure of dtBBP·CLA at 100 K. ► We detected a phase transition at 414 K in the complex and postulated its mechanism. ► We interpreted the infrared spectra of dtBBP·CLA. ► We used DFT to calculate the molecular structure of dtBBP·CLA in solid state.