Pendant amine bases speed up proton transfers to metals by splitting the barriers.

Division of Theoretical Chemistry & Biology, School of Biotechnology, KTH Royal Institute of Technology, 106 91 Stockholm, Sweden.
Chemical Communications (Impact Factor: 6.38). 03/2012; 48(37):4450-2. DOI: 10.1039/c2cc00044j
Source: PubMed

ABSTRACT By using density functional theory on [FeFe]-hydrogenase mimics we deconvolute the function of pendant amine bases in proton transfer to and from the metal center. By dividing the high free energy barrier into one high enthalpy-low entropy barrier and one with a low enthalpy-high entropy, a lower free energy barrier is reached.

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Ying Wang