Molecular dynamics and electric conductivity process efficiency in an anhydrous system. 1H NMR study of benzimidazolium azelate

•1H NMR results are correlated with proton conductivity and crystal structure.•The microscopic model of BenAze conductivity is proposed.•The proton conduction process efficiency is limited by the molecular dynamics.•The proton transfer path in the bulk of BenAze sample is proposed.

Benzimidazolium azelate (abbreviated as BenAze) and benzimidazole (abbreviated as Ben) are generally assumed as model compounds to study a relationship between the hydrogen bond network, molecular dynamics and the electric conductivity process efficiency in an anhydrous system. 1H NMR results correlated with those of proton conductivity and crystal structure have shown that conduction of BenAze crystal is a cooperative process involving both molecular motions prior to the proton exchange and migration along the hydrogen bonded chain. The microscopic model of BenAze conductivity as well as proton transfer path is proposed. It is also shown that efficiency of proton conduction process is limited by restrictions in the motion of benzimidazole molecules.