Temperature induced proton transfer in a hydrogen bonded supramolecule

Thermally controlled characteristic proton-transfer dynamics are realized with the hydrogen bonded 1D chain of non-polar π-conjugated dicarboxylic acid and bipyridine. The mutual dispositions of the juxtaposed chains are additionally determined by bridging water molecules other than C–H⋯O and π–π stacking interactions. Temperature and frequency dependent dielectric measurements revealed the phase transition at Tc = 333 K. Large deuteration effect and variable temperature UV and IR spectroscopic results amply support the proton transfer concomitant with phase transition. Differential scanning calorimetric (DSC) measurement again reconciles the temperature anomaly due to second-order phase transition in agreement with the temperature-dependent dielectric measurements.