jp0c01962_si_001.pdf (1.22 MB)
Download fileStructural Phase Transition of Ruthenium Cluster Hydrides
journal contribution
posted on 2020-06-23, 16:14 authored by Anna-Sophia Hehn, Dennis Bumüller, Wim Klopper, Manfred M. Kappes, Detlef SchoossWe
present a study of the structural effects of hydrogen adsorption
on Ru14– investigated
by a combination of trapped ion electron diffraction and density functional
computations. While the bare Ru14– forms a double layer hexagonal structure,
the adsorption of hydrogen initiates an evolution of the metal core
toward an icosahedral structure. The structural rearrangement is driven
by the difference in mean hydrogen adsorption energies, gradually
stabilizing the icosahedral cluster core structure for higher hydrogen
coverage. Detailed temperature dependent measurements reveal a crossover
between the two structure motifs and indicate a structural phase equilibrium.
Accompanying free energy computations confirm the chemical equilibrium
and identify a hydrogen coverage instability region where the cluster
hydrides decompose into the two core isomers with different hydrogen
coverage.