CSGB 2024 | U.S. DOE Office of Science(SC)

Structure of Iridium (Ir) dimer complex showing an Ir-Ir bonding molecular orbital populated (left) and an Ir-Ir anti-bonding molecular orbital depopulated (right) by optical excitation.

Advanced Techniques Paint a More Accurate Picture of Molecular Geometry in Metal Complexes

Ultrafast X-ray scattering and advanced numerical simulations decode distinct molecular structures and their equilibration dynamics in metal-metal complexes.

A long-predicted ultrafast isomerization in the UV photochemistry of bromoform is visualized for the first time by femtosecond time-resolved electron diffraction. At 267 nm excitation, the reaction pathway surpasses direct dissociation by a 60:40 margin.

Bromoform Molecules Like to Rearrange Their Atoms

Ultrafast electron diffraction imaging reveals atomic rearrangements long suspected to be crucial in the photochemistry of bromoform.

Researchers retrieved the time-varying molecular structure of photoexcited o-nitrophenol from ultrafast electron diffraction data using a genetic algorithm

Speedy Nuclei Do the Twist

Ultrafast electron imaging captures never-before-seen nuclear motions in hydrocarbon molecules excited by light.

Copper X-ray absorption spectroscopy measurements of catalysts in action demonstrate light-driven oxidation of copper nanoparticles under photocatalytic operating conditions.

X-ray Measurements Reveal an Unexpected Role for Copper in Photocatalysts

Copper catalysts play an unexpected oxidizing role during unassisted photocatalysis when coupled with plasmonic light absorbers.

A gas-phase X-Ray scattering experiment captures cyclopentadiene rapidly transforming into the strained bicyclo[2.1.0]pentene. This structure change is triggered by a pump pulse (blue) and detected through X-ray scattering (yellow).

Carbon Rings Under Stress

Ultrafast X-ray experiments provide direct evidence that interaction of light with a hydrocarbon molecule produces strained molecular rings.

Shale is physically and chemically complex at all scales of interest. Multimodal, multiscale imaging, and characterization allows researchers to study how to control the transport and reactivity of matter inside complex porous structures such as shale.

Scientists Characterize Shale Cap Rocks at Tiny Scales

Years of basic scientific research crosscutting multiple disciplines produces new information on the nanoscale complexities of shale.

Nanocrystals (left) capture light (hv) and then transfer electrons (e-) to nitrogenase enzymes (upper right) to convert dinitrogen (N2) to ammonia (NH3). A sacrificial reaction (bottom right) completes the process.

Powering Enzymes with Light to Make Ammonia

Scientists examine how molecular systems made of nanocrystals and proteins support the production of ammonia using light.