Probing the vibrations of shared, OH+O-bound protons in the gas phase

Spectral signature of a proton bridge? Gas-phase infrared spectra are reported in the range of 500 - 1800 cm-1 for three species with short, strong hydrogen bonds, namely the proton-bound dimers of dimethyl ether (shown in the picture) and diethyl ether, and protonated 1,1′ -oxybis[2-methoxyethane] (diglyme). The spectra are all quite similar, and furthermore they also strongly resemble the spectrum of the proton-bound water dimer (H5O2+), suggesting that there may be a conserved spectral signature" for a proton bound between two oxygen atoms."