A two-dimensional molecular network structure of trimesic acid prepared by adsorption-induced self-organizationElectronic supplementary information (ESI) available: materials and methods. See http://www.rsc.org/suppdata/cc/b2/b207556c/

Abstract

A two-dimensional molecular network of trimesic acid on Au(111) was visualized by in situ scanning tunneling microscopy with submolecular resolution. The supramolecular structures including an 'order to order' phase transition were constructed by precise potential-controlled adsorption based on adsorption-induced self-organization.

Templated Growth of Metal–Organic Coordination Chains at Surfaces

“…[23,24,26] Depositing at lower temperatures, 210 K and 250 K, resulted in disordered structures with a tip to tip bonding motif. This signature which is never observed above 300 K is characteristic for intramolecular dimeric hydrogen bonds of carboxylic groups, [20][21][22]24] thus indicating that the carboxylic groups are protonated for temperatures below 300 K. Annealing to 300 K of these structures yields to the same 1D chains described above. The 300 K chains typically show irregular kinks and poor long-range order.…”

“…Following previous analysis, [9,10,[20][21][22] the triangles are identified as flat-lying TMA molecules. The round protrusions can be attributed to Cu adatoms, [7,9,10] coordinated by two of the carboxylate groups of the TMA molecule.…”

“…In order to evidence its strong 1D templating effect on organic molecules, a ligand with a triangular symmetry was selected: 1,3,5-benzenetricarboxylic acid (trimesic acid, TMA, Figure 1c). In fact, the 3-fold rotation symmetry supports the formation of hexagonal 2D and 3D architectures, [20][21][22] therefore strongly disfavoring the linear geometry. On the isotropic Cu(100) surface, TMA forms 0D carboxylate complexes and 2D networks.…”

Hydrogen and Coordination Bonding Supramolecular Structures of Trimesic Acid on Cu(110)

“…These STM observations suggest that at 130 K, the acid groups of TMA are at least partially intact and that hydrogen bonding is the dominant intermolecular interaction at this temperature. 24,49,51,53 B. IR Measurements. Figure 3 shows a series of infrared (IR) spectra as a function of increasing coverage during TMA deposition on Cu(110) at 85 K. For low coverage (spectra a-c), the main bands are found at 743, 940, 1427, and 1643 cm -1 .…”

“…34,35 A typical linker molecule used for surface MOCNs is trimesic acid (TMA) comprised of three carboxylic acid groups ordered in a planar triangular arrangement around the central phenyl ring, Figure 1. TMA has been investigated in its acidic form in solids 46,47 as a three-dimensional MOCN coordinated to Cu ions 23, 48 and on low reactivity surfaces, 12,14,[49][50][51][52][53][54][55] where mostly hexagonal honeycomb networks are found, which are formed by intermolecular hydrogen bonding. However, in its deprotonated form, the carboxylate groups may combine with metal atoms to form extended metal-organic coordination networks in three dimensions in the solid state 48,56,47 and on surfaces in two [24][25][26]28 and one dimensions.…”