Computational Comparative Analysis of Small Atomically Precise Copper Clusters.

Area of Science:

• Materials Science
• Nanotechnology
• Computational Chemistry

Background:

• Atomically precise copper clusters (APCs) are vital for sensing, water remediation, and electrochemical applications.
• Understanding the properties of smaller APCs and their size/composition dependence is crucial but limited.
• Existing research lacks detailed insights into structure-property relationships for small APCs.

Purpose of the Study:

• To investigate the electronic structure, geometry, and optical properties of small atomically precise copper clusters.
• To analyze how ligand modifications and anchor atom changes influence APC characteristics.
• To explore the effect of increasing copper core size on cluster properties.

Main Methods:

• Density Functional Theory (DFT) calculations.
• Time-dependent DFT (TD-DFT) for optical properties.
• Comparative analysis of computational and experimental data.

Main Results:

• Experimentally observed Cu4 clusters exhibit a closed-shell superatom electronic structure (1S21P2).
• Ligand variations on Cu4 clusters showed minimal impact on core geometry, electronic structure, or optical spectra.
• Anchor atom modification increased the electronic gap and caused a hypsochromic shift; increasing core size led to smaller electronic gaps and bathochromic shifts.

Conclusions:

• Computational studies provide valuable physical insights into APC behavior.
• Changes in anchor atoms and core size are key factors tuning APC electronic and optical properties.
• This work aids in identifying small atomically precise nanocluster compositions from experimental data.