Supramolecular Tiling of a Conformationally Flexible Precursor

Area of Science:

• Supramolecular chemistry
• Materials science
• Surface science

Background:

• Supramolecular self-assembly is a key method for nanopatterning.
• Molecular tiling, particularly Kagome lattices, offers unique chemical and physical properties.
• Controllable fabrication of complex, distorted Kagome lattices remains challenging.

Purpose of the Study:

• To demonstrate the controllable fabrication of 2D distorted Kagome lattices.
• To tune metastable phases through deposition rates.
• To understand the kinetic control over lattice formation.

Main Methods:

• Utilizing a conformationally flexible precursor, 2,4,6-tris(3-bromophenyl)-1,3,5-triazine (mTBPT).
• Employing supramolecular self-assembly on a cold Ag(111) substrate.
• Combining scanning tunneling microscopy (STM) and density functional theory (DFT) calculations.

Main Results:

• Achieved two-dimensional distorted Kagome lattice p3,(333) formation.
• Tuned metastable phases, including homochiral porous networks, by controlling deposition rates.
• Identified surface kinetics as the primary factor governing the formation of energetically unfavorable distorted Kagome lattices.

Conclusions:

• Conformationally flexible mTBPT molecules enable controllable growth of diverse supramolecular phases.
• Metastable Kagome lattices can be trapped by manipulating deposition rates and surface kinetics.
• This approach offers a pathway for designing and fabricating complex nanopatterns with tunable properties.