Comment on 'Structural characterization, reactivity and vibrational properties of silver clusters: a new global minimum for Ag-16' by P. L. Rodriguez-Kessler, A. R. Rodriguez-Dominguez, D. MacLeod Carey and A. Munoz-Castro, Phys. Chem. Chem. Phys., 2020, 22, 27255, DOI: D0CP04018E

A recent paper by Rodríguez-Kessler et al., Phys. Chem. Chem. Phys., 2020, 22, 27255-27262, reported not only results of quantum chemical computations (using the PW91 density functional) on Ag16 clusters as emphasized in the article's title, but also on the Ag15 size. These authors confirmed previous results obtained by McKee and Samokhvalov (J. Phys. Chem. A, 2017, 121, 5018-5028 using the M06 density functional) that the most stable isomer of Ag15 is a C2v structure. We wish to point out that two low symmetry isomers of Ag15 that have a similar energy content are even lower in energy than their reported C2v global minimum. The relative energies between low-lying Ag15 isomers were again found to be method-dependent, and within the expected accuracy of DFT and CCSD(T) methods they could be considered as energetically degenerate, and likely coexist in a molecular beam. The new lower-energy Ag15 isomers appear to fit more consistently within the structural evolution of small silver clusters.

Publication year:2021