Structural transformations in Cu, Ag, and Au metal nanoclusters.

Area of Science:

• Computational materials science
• Nanotechnology
• Physical chemistry

Background:

• Understanding the finite-temperature behavior of metal nanoclusters is crucial for their applications.
• Previous methods struggled to accurately model nanocluster structures across the entire temperature range.

Purpose of the Study:

• To investigate the temperature-dependent structural evolution of Cu, Ag, and Au nanoclusters.
• To analyze the competition between different structural motifs in nanoclusters.
• To identify system-specific differences in structural behavior.

Main Methods:

• Utilized a novel computational methodology combining Harmonic Superposition Approximation (HSA) and Parallel Tempering Molecular Dynamics (PTMD).
• HSA provides accuracy at low temperatures, while PTMD effectively samples high temperatures and melting.
• Studied nanoclusters in the size range of 1-2 nm.

Main Results:

• Identified three main types of structural changes: dominant global minimum, complete solid-solid transformation, or partial transformation with co-existing motifs.
• Observed size- and system-dependent competition between structural motifs.
• Highlighted distinct structural differences among Cu, Ag, and Au nanoclusters.

Conclusions:

• The combined HSA-PTMD method accurately models nanocluster structures across a wide temperature range.
• Metal nanocluster structural transformations are complex and depend on temperature, size, and material.
• This work provides insights into the fundamental behavior of coinage metal nanoclusters.