Searching for stable copper borozene complexes in CuB₇^- and CuB₈

Area of Science:

• Materials Science
• Computational Chemistry
• Surface Science

Background:

• Borophene synthesis relies on specific substrates, with copper being a key material.
• Understanding copper-boron interactions is crucial for elucidating borophene growth mechanisms.
• Copper-boron binary clusters serve as model systems for these interactions.

Purpose of the Study:

• To investigate the structural and bonding properties of copper-doped boron clusters, specifically CuB7- and CuB8-.
• To provide insights into the fundamental interactions between copper and boron relevant to borophene growth.

Main Methods:

• Joint photoelectron spectroscopy and theoretical calculations were employed.
• Photoelectron spectra were obtained for CuB7- and CuB8- at various wavelengths.
• Theoretical methods were used to analyze cluster structures and bonding characteristics.

Main Results:

• CuB8- was identified as a stable borozene complex with a half-sandwich structure (Cu+ interacting with η8-B82-).
• CuB7- features a terminal copper atom bonded to a double-chain B7 motif, with a low-lying isomer exhibiting a half-sandwich structure (Cu+ interacting with η7-B72-).
• Both ionic and covalent interactions were observed in the binary Cu-B clusters, leading to diverse structures.

Conclusions:

• The study elucidates the distinct structural motifs and bonding behaviors of CuB7- and CuB8- clusters.
• The findings contribute to a deeper understanding of copper-boron interactions and their role in borophene formation.
• The observed structural diversity highlights the complex interplay of ionic and covalent bonding in these binary clusters.