2H Solid-State NMR of Mobile Protons: It Is Not Always the Simple Way

A combined study of 2 H line-shape analysis and ab initio molecular dynamics simulations was carried out on poly[vinyl phosphonic acid] (a water-free proton conducting material). We can elucidate the geometry and even time scale of the complex motional process, where dynamical proton motion occurs via the rearrangement of H-bonding networks, involving both intra- and interchain transfers.