Geometric structures of Ge(n) (n=34-39) clusters.

Area of Science:

• Materials Science
• Computational Chemistry
• Condensed Matter Physics

Background:

• Understanding the atomic structure of germanium clusters is crucial for predicting their properties.
• Previous studies have explored smaller germanium clusters, but the structural evolution of medium-sized clusters remains an active research area.

Purpose of the Study:

• To determine the lowest-energy structures of germanium clusters with sizes ranging from 34 to 39 atoms (Ge(n), n=34-39).
• To investigate the structural transition from prolate to Y-shaped configurations in these germanium clusters.

Main Methods:

• Utilized a genetic algorithm with a tight-binding interatomic potential to search for candidate structures.
• Employed first-principles calculations based on density functional theory (DFT) for accurate structural identification and energy minimization.

Main Results:

• Identified that Ge(n) (n=34-39) clusters predominantly form prolate or Y-shaped three-arm structures.
• These structures are composed of smaller stable clusters (Ge(6), Ge(7), Ge(9), Ge(10)) linked by Ge(6) or Ge(9) bulk units.
• The transition from prolate to Y-shaped structures was predicted to occur at Ge(35) or Ge(36) clusters.

Conclusions:

• The structural preferences of medium-sized germanium clusters are dictated by the assembly of smaller stable subunits.
• The observed transition point provides insight into the size-dependent structural evolution of germanium clusters.
• These findings contribute to a deeper understanding of nanoscale germanium structures and their potential applications.