Rotation in an Enantiospecific Self‐Assembled Array of Molecular Raffle Wheels

Abstract

Tailored nano-spaces can control enantioselective adsorption and molecular motion. We report on the spontaneous assembly of adynamic system-a rigid kagome network with each pore occupied by ag uest molecule-employing solely 2,6-bis(1H-pyrazol-1-yl)pyridine-4-carboxylic acid on Ag(111). The network cavity snugly hosts the chemically modified guest, bestows enantiomorphic adsorption and allows selective rotational motions.T emperature-dependent scanning tunnelling microscopys tudies revealed distinct anchoring orientations of the guest unit switching with a0.95 eV thermal barrier.H -bonding between the guest and the host transiently stabilises the rotating guest, as the flapper on ar affle wheel. Density functional theory investigations unravel the detailed molecular pirouette of the guest and how the energy landscape is determined by H-bond formation and breakage.The origin of the guestse nantiodirected, dynamic anchoring lies in the specific interplay of the kagome network and the silver surface.

Substrate Tumbling in a Chemisorbed Diastereomeric α‐Ketoester/1‐(1‐Naphthyl)ethylamine Complex

“…The combined effect is to permit MTFP to rotate both in and out of the surface plane without undergoing decomplexation or desorption. Papageorgiou and co‐workers [20] recently reported on H‐bond hindered in‐plane rotation in cavities in an organic network on Ag(111). In their work, time‐lapsed STM imaging revealed stepped rotation of a molecule bearing a carboxyl group in cavities containing three carboxylate anchoring points.…”

Self-Accommodating Honeycomb Networks from Supramolecular Self-Assembly of s-Indacene-tetrone on Silver Surfaces

“…[9][10][11] In some cases, the system can be self-accommodating, i.e. incorporate some of the frame molecules (host) as guest, [12][13][14] as it is the case occasionally for example with the various porous networks formed by trimesic acid. [15][16][17] In this work we were interested in a particular type of self-accommodating honeycomb network, for which the nanopores are systematically filled in a periodic fashion.…”

“…Supramolecular self-assembly of small planar aromatic molecules at surfaces can provide a tremendous variety of nanostructures by taking advantage of weak and reversible intermolecular interactions, as revealed at the single-molecule level by scanning probe microscopy. − Among the various tessellation patterns that can be created, the honeycomb network is particularly attractive due to its nanoporosity, ,, leading to confinement effects or potentially representing a prototypical system of host–guest molecular complexes. − In some cases, the system can be self-accommodating, i.e., incorporate some of the frame molecules (host) as the guest, − as is the case occasionally, for example, with the various porous networks formed by trimesic acid. − In this work, we were interested in a particular type of self-accommodating honeycomb network, for which the nanopores are systematically filled in a periodic fashion. In the resulting complex hierarchical patterning, the guest molecules are becoming entirely involved in the self-assembly of the honeycomb framework and contribute to the stability of the whole pattern.…”

Supramolecular Tiling of a Conformationally Flexible Precursor

“…In particular, trihexagonal tiling, also known as the Kagome lattice, is significant for potential applications in catalysis, , electronics, , and magnetics due to its physical (flat bands) and chemical properties. , Among Kagome lattice systems making use of noncovalent interactions at the molecular level, employment of conformationally rigid precursors is a universal method because the symmetry element of rigid precursors determines the geometric superstructures of the molecular Kagome lattice. − The geometrically distorted Kagome lattices are topologically equivalent tilings with low symmetry. ,− However, the construction of distorted Kagome lattice is challenging owing to the geometrical complexity, especially the metastable distorted Kagome lattice. Molecular tectons with reduced symmetries may be used to construct sophisticated two-dimensional supramolecular nanostructures, including fractals, − random glasses, , and some intricate tilings. − Therefore, a common strategy is needed to achieve the bottom-up construction of the distorted Kagome lattice using the conformationally flexible precursor.…”