Theoretical study of correlations between the coordination structures and catalytic activities in polymer‐stabilized au nanocluster catalysts.

Au nanoclusters (Au NCs) stabilized by poly(N‐vinyl‐2‐pyrrolidone) and poly(allylamine), abbreviated to Au:PVP and Au:PAA, catalyze the aerobic oxidation of p‐hydroxybenzyl alcohols, but the catalytic activity of Au:PVP is much higher than that of Au:PAA. To elucidate the correlations between the catalytic activities and coordination structures of the stabilizing polymer, the substrate accessibility on Au NCs was estimated by density functional theory (DFT) and molecular dynamics (MD) calculations. For MD simulations, we applied a systematic method to optimize the temperature parameters in temperature replica exchange molecular dynamics (T‐REMD), and the coordination structures were comprehensively classified by multivariate analysis. The results show that the number of open active sites on the Au NCs is a good index for predicting the catalytic activities. © 2018 Wiley Periodicals, Inc. The authors investigated the coordinate structures of polymer‐stabilized Au nanocluster (Au NC) in association with catalytic activity by using the Au NC surface coverage ratio by the polymers. The results indicate that the relative catalytic activities of polymer‐stabilized Au NCs can be largely predicted by estimating the number ratio of the adsorbed monomer molecules on Au NC by DFT calculation, when the lengths of the polymer chains are almost the same. [ABSTRACT FROM AUTHOR]