Single and relayed proton transfer in peptide

We next study water-assisted (relayed) proton transfer in formamide, comparing with a forced proton transfer within formamide in gas phase (Fig. 7.10), which are also associated with the tautomerization. We start from the enol (imidic acid) form HO-CH=NH and track the transfer process to the keto (amide) form 0=CH-NH2. We first survey the above very basic puzzles with this system, identifying that this is indeed a proton 

Chemical Theory Beyond the Born-Oppenheimer Paradigm 

Bohr 2, respectively. Water molecules are indicated as a pair of black thin lines, each representing an OH bond. FVom left to right, times are t = 0.25, t = 19.00 and t = 40.00 (in units of fs). This figure should be compared to the undeuterized counterpart. Fig. 7.6. (Reprinted with permission from T. Yonehara et al., Chem. Rev. 112, 499 (2012)). 

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