Hydride Migration within RhH₂Ag₁₉ Superatom: A Combined Neutron Diffraction and DFT Analysis

Area of Science:

• Inorganic Chemistry
• Materials Science
• Computational Chemistry

Background:

• Metal nanoclusters exhibit unique properties due to their size and structure.
• Understanding atom dynamics within these clusters is crucial for material design.
• Hydride mobility influences reactivity and potential applications like hydrogen storage.

Purpose of the Study:

• To determine the most likely hydride migration pathway in the [RhH2Ag19{S2P(OnPr)2}12] (RhH2Ag19) nanocluster.
• To computationally analyze the energetic favorability of identified pathways.
• To provide insights into the structural flexibility and dynamics of superatom frameworks.

Main Methods:

• Combining experimental neutron diffraction data with Density Functional Theory (DFT) calculations.
• Analyzing experimentally derived solid-state structures.
• Computational modeling to reveal energetically favorable migration pathways.

Main Results:

• An energetically favorable hydride migration pathway was identified.
• The maximum energy barrier for hydride migration was calculated to be 4.2 kcal mol⁻¹.
• Two hydrides were observed to migrate simultaneously within the Rh@Ag12 icosahedral core, passing through positional isomers.

Conclusions:

• The study elucidates the mechanism of hydride dynamics in metal nanoclusters.
• Findings offer critical insights into the structural flexibility of superatom frameworks.
• Results have significant implications for hydrogen storage, catalysis, and advanced hydride material development.