Hydride Migration within RhH ₂ Ag ₁₉ Superatom: A Combined Neutron Diffraction and DFT Analysis

An investigation combining neutron diffraction and DFT allows determining the most likely hydride migration pathway within the icosahedral metal framework of [RhH₂Ag₁₉{S₂P(OⁿPr)₂}₁₂] (RhH₂Ag₁₉). Starting from the experimentally derived solid-state structures, a computational analysis is able to reveal an energetically favorable migration pathway with a maximum energy barrier of 4.2 kcal mol^-1. The two hydrides migrate simultaneously within the Rh@Ag₁₂ icosahedral core, traversing several positional isomers. This study expands the understanding of hydride dynamics in nanoclusters and provides critical insights into the structural flexibility of the superatom framework. These findings have significant implications for hydrogen storage, catalysis, and the design of advanced hydride-containing materials.