Structure and layer interaction in carbon monofluoride and graphane: a comparative computational study.

Area of Science:

• Materials Science
• Computational Chemistry
• Condensed Matter Physics

Background:

• Carbon monofluoride (CF)(n) and graphane share related chemical motifs as 2D polycyclic hydrocarbons.
• Experimental structural data for (CF)(n) and graphane is often ambiguous or limited.
• Understanding their precise structures is crucial for material applications.

Purpose of the Study:

• To computationally investigate the structures of (CF)(n) and graphane in monolayer and stacked configurations.
• To elucidate the similarities and differences in their conformational energetics and layer arrangements.
• To develop a molecular mechanics force field for (CF)(n) and explain experimental observations.

Main Methods:

• First-principles density functional theory with nonlocal functionals for dispersion interactions.
• Quantum chemical calculations for conformational analysis and stacking.
• Development and application of a molecular mechanics force field within the OPLS/AA framework.
• Classical molecular dynamics simulations.

Main Results:

• Identified strong qualitative and quantitative similarities between (CF)(n) and graphane.
• Discovered a novel "gauche-chair" conformational motif.
• Developed a highly accurate force field for (CF)(n) that reproduces quantum chemical results.
• Proposed conformational disorder as an explanation for experimental lattice constant and interlayer distance variations.

Conclusions:

• Carbon monofluoride and graphane exhibit significant structural similarities.
• Conformational disorder provides a unified explanation for experimental structural anomalies in these 2D materials.
• The developed force field enables accurate large-scale simulations of (CF)(n).