Simulating ice nucleation, one molecule at a time, with the 'DFT microscope'.

Area of Science:

• Physical Chemistry
• Surface Science
• Computational Materials Science

Background:

• Ice nucleation is a ubiquitous physical process, yet its atomic-level mechanisms, especially heterogeneous nucleation, remain unclear.
• Understanding water-metal interactions is key to explaining ice formation on surfaces.

Purpose of the Study:

• To investigate water clustering and ice nucleation on a hydrophobic metal surface using computational methods.
• To provide a fundamental understanding of water-substrate interactions at the atomic scale.

Main Methods:

• Employed density functional theory (DFT) calculations to model water clusters.
• Computed possible structures for adsorbed water clusters (2-6 molecules) on a Cu(111) surface.
• Analyzed the differences between gas-phase and adsorbed water clusters and their substrate interactions.

Main Results:

• Identified and computed structures for small water clusters (2-6 molecules) adsorbed on the Cu(111) surface.
• Characterized the distinct structural and energetic properties of these adsorbed clusters compared to gas-phase clusters.
• Elucidated the nature of the interaction between water clusters and the metallic substrate.

Conclusions:

• DFT calculations offer a robust approach to understanding water nucleation on metal surfaces.
• Adsorbed water clusters exhibit unique structures and substrate interactions, differing from their gas-phase counterparts.
• This work lays a foundation for further atomic-level investigations into heterogeneous ice nucleation.