Structural evolution and electronic properties of neutral and anionic TiASi (A = Sc, Ti; l ≤ 12): relatively stable...

Area of Science:

• Computational chemistry
• Materials science
• Solid-state physics

Background:

• Understanding the structural and electronic properties of metal-silicon clusters is crucial for developing novel semiconductor materials.
• Titanium (Ti) and Scandium (Sc) alloyed silicon clusters offer potential for unique electronic and catalytic applications.

Purpose of the Study:

• To investigate the structural evolution and electronic properties of TiASi clusters and their anions.
• To identify the fundamental building blocks and stability trends within these clusters.
• To elucidate the chemical bonding responsible for the stability of specific cluster structures.

Main Methods:

• Simulated photoelectron spectroscopy was employed.
• Density functional theory calculations using the Perdew-Burke-Enzerhof (PBE) functional were performed.
• Extensive cluster structure searches were conducted using the ABCluster software.

Main Results:

• Ground-state structures of TiASi clusters generally showed similar configurations, with TiASi4 units identified as the basic framework.
• Cluster structures evolved from exohedral to cage-like with increasing size.
• Neutral TiASi4 clusters demonstrated enhanced stability compared to other neutral and anionic TiASi clusters.
• Analysis of Ti2Si4 revealed spd orbital hybridization, localized, and delocalized bonds contributing to its stability.

Conclusions:

• The TiASi4 cluster unit serves as a fundamental building block for larger TiASi clusters and their anions.
• Neutral TiASi4 clusters exhibit significant stability, making them promising candidates for silicon-based semiconductor applications.
• The findings provide insights into the design principles for novel metal-silicon nanostructures.