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Spin Saturation Transfer Difference NMR SSTD NMR: A New Tool to Obtain Kinetic Parameters of Chemical Exchange Processes
Published on: November 12, 2016
Reply to Comment on "Using NMR to Test Molecular Mobility during a Chemical Reaction"
Tian Huang1, Huan Wang2, Steve Granick1,3
1Center for Soft and Living Matter, Institute for Basic Science (IBS), Ulsan 44919, South Korea.
Abstract:
Reports of boosted diffusion during chemical and enzymatic reactions have inspired a loyal community of scientists who find them so counterintuitive that they must be artifact. This second Comment on the subject by these authors is about technicalities of how to analyze data we deposited online regarding J. Phys. Chem. Lett. 2021 12, 2370 and Science 2020 369, 537. Now that their own data is also online, one apparent discrepancy can be resolved: we demonstrate that the authors' data agrees with ours because their first Comment on this subject reported only truncated short-time excerpts of the longer time series they deposited online (zenodo.org/record/4628353). This second Comment adds five additional objections, four of which are too technical to change the qualitative conclusion. The fifth objection errs because it omits recognizing intermediate states of the click reaction during which one reactant complexes with the catalyst to form an object of larger size. Elsewhere we analyzed in great detail the respective influences of boosted diffusion and this hydrodynamic effect (DOI: 10.26434/chemrxiv.14740563.v1). The factual evidence and reasoning in this Reply strongly support this laboratory's earlier conclusions regarding boosted diffusion during common chemical reactions.
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