Predicting bilayer B₅₀, B₅₂, B₅₆, and B₅₈: structural evolution in bilayer B₄₈-B₇₂ clusters

Area of Science:

• Computational Chemistry
• Materials Science
• Nanotechnology

Background:

• Boron nanoclusters exhibit diverse structures like planar, cage-like, seashell-like, and bilayer forms.
• Experimental observations cover boron clusters (Bn-/0) from n=3 to 48, highlighting their rich chemistry.

Purpose of the Study:

• To predict and characterize novel bilayer boron nanoclusters (Bn) in the B48-B72 size range.
• To identify the global minima structures for specific boron cluster systems.

Main Methods:

• Extensive global minimum searches.
• Density Functional Theory (DFT) calculations.
• Detailed bonding analyses.

Main Results:

• Prediction of bilayer C1 B50 (I), C2h B52 (II), C1 B56 (IV), and C2v B58 (V) as global minima.
• Identification of a central B38 bilayer hexagonal prism in these stable species.
• Demonstration of enhanced stability for C1 B50 and C1 B56 compared to previous quasi-planar structures.
• Observation of universal σ + π double delocalization, indicating 3D aromaticity.

Conclusions:

• The predicted bilayer boron clusters fill a crucial gap in the B2n series (B48-B72).
• These stable nanoclusters exhibit unique structural and electronic properties, including 3D aromaticity.
• The findings contribute to understanding the structural evolution and bonding patterns of boron nanoclusters.