Title: Imaging structural transitions in organometallic molecules on Ag(100) for solar thermal energy storage,
Abstract: The use of opto-thermal molecular energy storage at the nanoscale creates new
opportunities for powering future microdevices with flexible synthetic
tailorability. Practical application of these molecular materials, however,
requires a deeper microscopic understanding of how their behavior is altered by
the presence of different types of substrates. Here we present single-molecule
resolved scanning tunneling microscopy imaging of thermally- and
optically-induced structural transitions in (fulvalene)tetracarbonyldiruthenium
molecules adsorbed onto a Ag(100) surface as a prototype system. Both the
parent complex and the photoisomer display distinct thermally-driven phase
transformations when they are in contact with a Ag(100) surface. This behavior
is consistent with the loss of carbonyl ligands due to strong molecule-surface
coupling. Ultraviolet radiation induces marked structural changes only in the
intact parent complex, thus indicating a photoisomerization reaction. These
results demonstrate how stimuli-induced structural transitions in this class of
molecule depend on the nature of the underlying substrate.