Dynamic hetero-metallic bondings visualized by sequential atom imaging.

Area of Science:

• Atomic and Molecular Dynamics
• Surface Science
• Computational Chemistry

Background:

• Traditional chemistry focuses on stable, isolable compounds.
• Computational chemistry highlights the importance of in situ dynamic atomic and molecular processes.
• Understanding transient species is crucial for advancing chemical synthesis and materials science.

Purpose of the Study:

• To directly visualize the formation and dissociation dynamics of labile atomic clusters.
• To achieve atomic resolution with elemental identification for transient species.
• To investigate the behavior of short-lived homo- and hetero-metallic dimers and trimers.

Main Methods:

• Utilized scanning transmission electron microscopy (STEM) for high-resolution imaging.
• Employed Z-contrast imaging for elemental identification of individual atoms.
• Recorded dynamic processes at low electron doses to minimize sample damage.

Main Results:

• Successfully visualized the real-time formation and dissociation of labile dimers and trimers.
• Directly observed short-lived metallic clusters, including AuAg, AgCu, and AuAgCu.
• Demonstrated the capability to identify elemental composition of transient atomic assemblies.

Conclusions:

• Direct atomic-level visualization of transient molecular species is achievable.
• This technique provides unprecedented insights into the dynamics of labile clusters.
• The findings open new avenues for studying and controlling short-lived chemical entities.