Proton transfer dynamics via high resolution spectroscopy in the gas phase and instanton calculations

摘要

Tunneling splittings have been observed in the eigenstate-resolved electronic spectrum of the 2-hydroxypyridine/2-pyridone dimer in the gas phase.Deuterium substitution experiments show that these splittings are caused by a concerted double proton transfer reaction along the O-H???O and N???H-N hydrogen bonds that hold the dimer together,substitution of the weaker and longer N???H-N bond having the larger effect.Tunneling splittings calculated by the instanton method for the zero-point level of the ground state are in good agreement with experiment for all observed isotopomers,showing that the dynamics occurs in this state,rather than in the electronically excited state.