[11]Anthrahelicene on InSb(001) c(8×2): A Low‐Temperature Scanning Probe Microscopy Study

Abstract

The adsorption of individual [11]anthrahelicene molecules and their self-assembly into monolayer islands on an InSb(001) c(8×2) reconstructed surface is studied with low-temperature scanning probe microscopy. A racemic mixture is deposited on atomically flat terraces of InSb at room temperature. At lower coverage, the molecules tend to decorate atomic step edges of the substrate. At higher coverage, [11]anthrahelicene molecules form 2D islands. A quasi-hexagonal ordering of molecules within the layer is identified. Furthermore, it is shown that molecules adsorb with the helical axis almost perpendicular to the substrate. Interference between tunneling through the molecular layer and directly through space is reported. Finally, experimental results are compared to those of theoretical calculations.

Mechanical tuning of conductance and thermopower in helicene molecular junctions

“…[40][41][42] Furthermore, as a first step towards realizing single-molecule junctions, helicenes have been placed on surfaces and probed with atomic force and scanning tunneling microscopes. [43][44][45][46][47][48][49][50] FIG. 1.…”

“…[40][41][42] Furthermore, as a first step towards realizing single-molecule junctions, helicenes have been placed on surfaces and probed with atomic force and scanning tunneling microscopes. [43][44][45][46][47][48][49][50] We suggest that the distance r between the two metallic electrodes of a helicene molecular junction (Fig. 1(b)) can be used as an experimental control parameter that can be tuned to alter and probe the properties of the HMJ.…”

Two-Dimensional Crystallization of Enantiopure and Racemic Heptahelicene on Ag(111) and Au(111)

“…On the other hand, 5-amino[6]helicene shows at the Au(111)/liquid interface a coexistence of a 2D conglomerate with a racemic phase . There are also studies of [11]anthrahelicene and hexathia[11]helicene on various substrates. − A spontaneous 2D resolution for a nonfunctionalized helicene has been reported so far only for dibenzo[5]helicene on gold(111) …”

Chiral expression of adsorbed (MP) 5-amino[6]helicenes: from random structures to dense racemic crystals by surface alloying

“…1 Carbohelicenes tend to form conglomerates in the solid state 12 while puzzlingly on surfaces only two examples of 2D conglomerate formation were reported so far. 13,14 Unfortunately, a few scattered studies of functionalized helicenes [15][16][17][18][19][20][21][22] are available and there is no clear trend on the influence of the heteroatoms on the chiral expression. Even less information is available regarding the role of the symmetry of the surface in the stereo structural outcome of the 2D assembly.…”