Temperature-Directed Hierarchical Surface Supramolecular Assembly

Abstract

The hierarchical organization of building blocks is an important characteristic of self-assembly. Herein, we report a series of triangular hierarchical assemblies formed by C 3 -symmetric 5,10,15-triethyl-10,15-dihydro-5H-diindolo[3,2a:3′,2′-c]carbazole-2,7,12-tricarbaldehyde (M1) on the graphite surface. The molecule assembles into a hexagonal array on the graphite surface at room temperature with a trimeric assembly motif as the basic building block of the hierarchical assembly. With the increase of annealing temperature, the sizes of triangles in hierarchical assemblies vary from large to small with the presence of antiparallelly arranged molecular dimers as building blocks at the triangular boundaries. The hierarchical-order-level-dependent intermolecular interaction and molecule−substrate interaction were modeled, and the entropy contributions of alkyl substitution at different temperatures were proposed to account for the observed structural evolution process. This work provides a new example of hierarchical assembly directed by temperature and is beneficial for the understanding of both the assembling process and the underlying kinetics and thermodynamics for hierarchical molecular nanostructures.

Surface supramolecular assemblies tailored by chemical/physical and synergistic stimuli: a scanning tunneling microscopy study

“…Temperature directs hierarchical surface self-assembly in which the size of the triangles varies from large to small with increased temperature, as demonstrated by Wang and co-workers, in C 3 -symmetric 5,10,15-triethyl-10,15-dihydro-5 H -diindolo[3,2- a :3′,2′- c ]carbazole-2,7,12-tricarbaldehyde (M3) self-assembly. 125 This molecule has a large planar aromatic core, through which it interacts favorably with the HOPG surface, three formyl groups, and three ethyl groups. As the temperature varies, complex triangular hierarchical assembly structures are observed (Fig.…”

Coverage‐Controlled Superstructures of C3‐Symmetric Molecules: Honeycomb versus Hexagonal Tiling

“…These upper limits may have various reasons including limited control of the coverage,kinetics,and surface inhomogeneities. Systems Dand Eactually exhibit different superstructures at Figure 4e xtracted from experimental observations (B-I and K-L) or fictitious( A, J [23,24,26] 0.98 30 2.33 [d] 1 8 [e] D [29] 1.10 28.5 2.14 [b] 1 12 [e] E [27] 1.00 15 3.06 1 8 F [28] 1.17 19.5 2.27 78 G [52] 1.17 48 2.73 55 [f ] H [53] 1.50 26 2.83 [b] 11 [e] I [30] 1.58 22 2.75 [a] 2 [g] 2 [g] J2 .00 [a] 22 2.75 [a] 1 K [25] 1.19 35 1.14 52 [e] L [31] 1.16 57 1.76 [b] 44 [f ] [a] Fictitious value.…”

Synthetic application of gold complexes on magnetic supports

“…Oxidative esterification is another form of esterification reaction; here instead of direct esterification that involves the reaction of an alcohol, the corresponding aldehyde is directly used instead of an acid, and as it is a one‐pot reaction, it proceeds without any problems or additional steps . This reaction is extensively studied for GNCs nanocatalysts .…”