Thermodynamic properties of Ga27Si3 cluster using density functional molecular dynamics

Area of Science:

• Computational materials science
• Cluster physics
• Thermodynamics

Background:

• Gallium clusters exhibit unique thermodynamic behaviors.
• Understanding impurity effects is crucial for materials design.

Purpose of the Study:

• To investigate the impact of silicon impurities on gallium cluster thermodynamics.
• To determine the ground state geometry and melting behavior of Ga(27)Si(3).

Main Methods:

• Density functional molecular dynamics simulations.
• Obtained 500 low-energy equilibrium geometries for Ga(27)Si(3).
• Calculated specific heat using multiple histogram techniques.

Main Results:

• Silicon impurities significantly affect the thermodynamic properties of Ga(30).
• Ga(27)Si(3) exhibits a clear melting peak around 500 K.
• The cluster transforms from a nonmelter to a melter due to silicon doping.

Conclusions:

• Silicon impurities fundamentally change the melting characteristics of gallium clusters.
• The study provides insights into impurity-induced phase transitions in nanoscale materials.