Bending moduli for forty-four select atomic monolayers from first principles

Area of Science:

• Materials Science
• Condensed Matter Physics
• Computational Chemistry

Background:

• Atomic monolayers offer unique mechanical properties.
• Understanding their bending rigidity is crucial for nanoscale device applications.
• Previous methods struggled to accurately calculate bending moduli in the low-curvature limit.

Purpose of the Study:

• To calculate bending moduli for 44 diverse atomic monolayers.
• To investigate the influence of material type, thickness, and lattice structure on bending rigidity.
• To explore the low-curvature limit using an advanced computational method.

Main Methods:

• Utilized ab initio density functional theory (DFT).
• Employed the recently developed Cyclic DFT method.
• Calculated bending moduli along principal directions for various material groups (e.g., Group IV, III-V, transition metal dichalcogenides).

Main Results:

• Bending moduli span three orders of magnitude across the studied materials.
• Moduli generally increase with monolayer thickness.
• Rectangular lattice structures exhibit higher anisotropy than honeycomb structures.
• Deviations from trends are linked to bonding strength and structural relaxation.

Conclusions:

• The study provides a comprehensive dataset of bending moduli for various atomic monolayers.
• Material thickness and lattice type are key factors influencing bending rigidity.
• Cyclic DFT is effective for calculating bending moduli in the low-curvature regime.