Substrate Effects in the Supramolecular Self-Assembly of 2,4,6-Tris(4

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C: Surfaces, Interfaces, Porous Materials, and Catalysis

Substrate Effects in the Supramolecular Self-Assembly of 2,4,6Tris(4-bromophenyl)-1,3,5-triazine on Graphite and Graphene Chunhua Liu, Ling Yang, Yan Wang, Shengbin Lei, and Wenping Hu J. Phys. Chem. C, Just Accepted Manuscript • DOI: 10.1021/acs.jpcc.8b02979 • Publication Date (Web): 23 May 2018 Downloaded from http://pubs.acs.org on May 24, 2018

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The Journal of Physical Chemistry

Substrate Effects in the Supramolecular Self-Assembly of 2,4,6-Tris(4-bromophenyl)-1,3,5-triazine on Graphite and Graphene Chunhua Liu†,Ling Yang†, Yan Wang†, Shengbin Lei*,†,#, Wenping Hu# †

School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin,

150080, P. R. China. E-mail: [email protected] #

Tianjin Key Laboratory of Molecular Optoelectronic Science & Collaborative Innovation

Center of Chemical Science and Engineering (Tianjin), Tianjin University, Tianjin, 300072, P. R. China. ABSTRACT: Two-dimensional (2D) self-assembly of star-shaped 2,4,6-tris(4-bromophenyl)1,3,5-triazine (BPT) molecule is investigated both on highly oriented pyrolytic graphite (HOPG) and single layer graphene (SLG) grown on a polycrystalline Cu foil. Scanning tunneling microscopy (STM) reveals that this molecule can form different self-assembling structures on these two different surfaces. Based on high-resolution STM images, we find that BPT molecules can form compact and loose assemblypatterns with different packing density on HOPG surface, and a porous structure with hexagonal-like cavities on SLG surface. A combination of STM and density functional theory (DFT)calculations elucidates the interplay of molecule-molecule and molecule-substrate interactions on the assembling behavior on both substrates.

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INTRODUCTION Molecular self-assembly is a powerful “bottom-up” strategy for nanofabrication of specific nanopatterns.1-5 Since the pioneering and effective studies, plenty of examples of 2D highly ordered supramolecular networks based on the non-covalent intermolecular interactions on surface have been reported.6Besides the structure of building blocks, other factors, such as solvent, concentration, temperature or external stimuli, also play important roles in influencing the self-assembling tailored buildingblocks.7-13 The successful formation of well-ordered twodimensional (2D) supramolecular networks always depend on the subtle balance between molecule-molecule and molecule-substrate interactions.14 Furthermore, strong moleculesubstrate interactions can even disrupt the growth of the supramolecular structures.15 A large number of studies about molecular surface adsorption indicate that substrates not only serve as physical support but also play a significant role in determining the adsorption unique directions and subsequent assembly behaviors.16 Supramolecular 2D networks are mainly stabilized by weak intermolecular interactions, such as hydrogen bonds,17 metal-ligand coordination,18 van der Waals forces,19-21 dipole-dipole interactions,22and π-π stacking,23etc. at the liquid/solid interface or a solid/vacuum interface.24 Though long been a focus in the field of molecular recognition, chiral separation, crystal engineering and supramolecular chemistry crystal engineering due to the peculiar double polarization of the carbon-halogen (C-X) bond,25-28 and halogen bonding (X-bonding) only start to come into the view of on-surface supramolecular assembly very recently.29-31 The polarization of halogen atom X (X=F, Cl, Br, I) in a C–X bond results in halogen bonds. Although its important role in 3D crystal engineering32,33 has been fully recognized, it is studied less extensively in 2D self-assembly at the liquid/solid interface34-36 or under ultra-high vacuum


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conditions.37,38 Compared with hydrogen bonds (H-bonds), the X-bond is expected to be highly directional and intrinsically more suitable for the assembly of semiconductors as it does not involve any acidic/basic centers that can trap charges.39 These advantages open up new opportunities for clipping supramolecular self-assembly construction and thus it is beneficial to design novel organic structures. Studying their arrangement and how these molecules interact with each other can thus be important for the understanding of organic electronic devices. Such non-covalent self-assembly derived from halogen bond thus provides an interesting new approach for development of organic electronic devices and supramolecular2D networks otherwise difficult to obtain. In the past few years, the star-shaped molecules with various central rings have been designed and synthesized owing to a growing interest in the 3-fold symmetric molecular structure.40-44 The end substituent groups of star-shaped molecule can be adjusted to fabricate special functional 2D organic nanoarchitectures on surfaces by exploiting intermolecular interactions. One of the most famous 3-fold symmetric molecule is 1,3,5-tris(4-carboxyphenyl)benzene, STM reveals that it can self-assemble into one close-packed structure and two other porous structures with hexagonal and rectangular cavities, which are all stabilized by intermolecular hydrogen-bonds. By controlling the external factors such as solvent and temperature, these assembling structures can be switched between each other controllably.39 More interestingly, this molecule can coassemble with other 3-fold symmetric building block, for instance, trimesic acid, into more complex architectures, which can be controlled by the concentration and molar ratio of both building blocks. 1,3,5-Tri(4′-bromophenyl)benzene is a promising precursor molecule for Ullmann coupling reaction,45 its self-assembling structures are different in ethanol and butanol.4648

1,3,5-tris(4′-iodophenyl)benzene can self-assemble into two different porous nanoarchitectures


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primarily depend on I···I bonds and van der Waals force.43 The halogen···halogen interactions have been turned out to be the main driving forces to form stable 2D self-assembly structures of 2,4,6-tris(4-bromophenyl)-1,3,5-triazine and 2,4,6-tris(4-iodophenyl)-1,3,5-triazinemolecules at the liquid/solid interface. The STM results have indicated that the Au(111) substrate exerts a much stronger effect than the nature of the bromine and iodine atoms.49 The2,4,6-tris(4',4'',4'''trimethylphenyl)-1,3,5-triazineself-assembles into close packed nanoarchitecture, which is stabilized by van der Waals interactions on HOPG.50 Porous networks have also been achieved using 1,3,5-tris(4′-biphenyl-4″-carbonitrile)benzene by metal-coordination.51 Therefore, starshaped molecules are expected to be a promising building block to fabricate organic nanoarchitectures at the interface. In this paper, we investigate in detail on the substrate effects of 2,4,6-tris(4-bromophenyl)1,3,5-triazine (BPT) by STM on highly oriented pyrolytic graphite(HOPG) and CVD grown single layer graphene (SLG) on copper foil at the liquid/solid interface. The STM results reveal that BPT can form densely-packed and loosely-packed arrangements on HOPG surface, and porous chicken wire networks appear to be the most stable structure on SLG. We also found that BPT molecule rows have a local shift at the domain boundary. On the basis of high-resolution STM images, we infer that on HOPG surface the main driving force of the two kinds of nanoarchitectures is the Br…H-C bonds interaction. For the porous chicken wire networks on SLG surface, it is mainly stabilized by threeBr…H-C bonds, a triple Br-Br-Br bond and strong molecule-substrate interactions together. The density functional theory (DFT) calculations on the assemblies provide some insight on the understanding of the stability of these architectures.


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Br

N

N N

Br

Br

Scheme 1. Chemical structure of 2,4,6-tris(4-bromophenyl)-1,3,5-triazine (BPT).

METHODS Experimental section: 2,4,6-tris(4-bromophenyl)-1,3,5-triazine (BPT) was purchased from Alfa Aesar and 1-octanoic acid was purchased from J&K, and were used without further purification. The non-covalent self-assembly of BPT was studied directly at the 1-octanoic acid/HOPG and 1-octanoic acid/SLG interface, respectively. Nearly saturated solutions of BPT in 1-octanoic acid were prepared. About 5 µL of the solution was drop-casted onto graphite or graphene substrates. A few minutes later, the self-assembled monolayer was characterized by scanning tunneling microscopy (STM). STM measurements were performed by using a Multimode 8 (Bruker, Germany) with mechanically cut Pt/Ir (80/20) tips at room temperature under ambient conditions. All images were taken in the constant current mode. The calibration of STM images was carried out by using an atomic resolution HOPG lattice. The chemical structure models were built with HyperChem software. Computational details: DFT calculations were performed using HF method with 6-31G** basis set for the simplified model, and using SVWN function with 3-21G basis set for C, N, and H atoms and 3-21G* basis set for Br atoms for the extended model.


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RESULTS AND DISCUSSION Non-covalent self-assembly of BPT at the octanoic acid/HOPG interface. The chemical structure of BPT is presented in Scheme 1. BPT is a star-shaped 3-fold symmetry molecule, the molecular skeleton consists three peripheral 4-bromophenyl groups connected by a central triazine ring. The molecule is expected to form dimers on the surface, as it was observed in the case of 1,3,5-tri(4′-bromophenyl)benzene molecules.52 Upon deposition of BPT on HOPG held at room temperature, well-defined supramolecular 2D patterns were observed by STM. Two different molecular arrangements have been revealed by means of in-situ STM: densely-packed arrangement (Figure 1a) and loosely-packed arrangement (Figure 1b), labeled as A-type and B-type, respectively. These two structures differ in their packing pattern and their particular packing density. Representative STM images of both structures are depicted in Figure 1 & Figure S1. The A-type nanoarchitecture is stabilized by Br…H-C bondand X4 halogen synthons (Br-Br-Br-Br)53 on graphite. A high-resolution STM image of the molecular nanoarchitecture is presented in Figure 1a. After calibration of the highresolution STM images against the underlying graphite lattice, the dimensions of the unit cell outlined are determined to be a = (2.2 ± 0.2) nm, b = (1.6 ± 0.2) nm and α = (70 ± 1)°. The unit cell of A-type packing contains two BPT molecules. The high-resolution STM image presented in Figure 1b shows the loosely-packed (B-type) structure which is composed also by BPT dimers. The dimer is stabilized by two Br···H bindings between neighboring molecules. The organic layer covers the entire graphite surface. The BPT dimer is composed of two BPT molecules rotated by 180° with respect to each other, as represented in Figure 1b. On the basis of this observation, a unit cell is marked in Figure 2b. According to this unit cell, the parameters are measured to be a = (2.5 ± 0.2) nm, b = (2.2 ± 0.2)


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nm and α = (70 ± 1)°. The unit cell contains one BPT dimer. Their corresponding tentative models are shown beside the STM images. As can be revealed both from the STM image and molecular model, the distance between BTP dimers are too large for van der Waals interaction, thus we suppose there are octanoic acid molecules coadsorbed with BTP in this assembly, high resolution STM image also reveals some bright features between the BPT dimers, which support our speculation.According to the unit cell parameters, the packing density of type-B is estimated to be 0.387 molecules·nm-2, while the packing density of A-type is 0.605 molecules·nm-2, as shown in Table 1.

Figure 1. STM images of BPTs self-assembled into A-type (a) and B-type (b) structure at the octanoic acid/HOPG interface. The corresponding tentative 2D packing models are both overlaid and shown beside the STM images. The tunneling conditions were Iset= 554 pA, Vbias = 390 mV.


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Table 1. Unit cell parameters of the self-assembling patterns of BPT.

α = 70 ± 1°

Unit cell area/ nm2 3.31

Packing density** /nm-2 0.605

b = 2.2 ± 0.2 nm

α = 70 ± 1°

5.17

0.387

b = 1.5 ± 0.2 nm

α= 60 ± 1°

1.95

0.513

Pattern

N*

Unit cell parameter

A-type

2

a = 2.2 ± 0.2 nm

b = 1.6 ± 0.2 nm

B-type

2

a = 2.5 ± 0.2 nm

C-type

1

a = 1.5 ± 0.2 nm

*N is the number of molecules in each unit cell. **Number of BPT (moiety) in each unit area.

The formation of domain boundary is dynamic at the octanoic acid/graphite interface, which can be directly revealed by STM. For instance, the dynamic self-assembly process of BPT is clearly recorded by a successive imaging as shown in Figure 2(a-c). At the liquid/solid interface, the formation and repairing of domain boundary occurs with the exchange of BPTs between the surface and supernatant solution. At first, in Figure 2a,the black arrow indicates a fuzzy area where no stable molecular adsorption on HOPG, i.e., molecules are mobile in this area. Then molecular assembly becomes clearly visible due to the formation/repairing of domain boundary in the successive image in Figure 2(b, c). The large-scale STM image in Figure 2d shows two kinds of unambiguous domain boundaries and three domains of molecular networks, which are defined as “I”, “II” and “III”. The domain boundaries are highlighted by two black dashed lines in Figure 2d. Another white dashed line through the three domains is superimposed to the STM image to guide the eye. It can be clearly seen in Figure 2d that domains “I” and “III” have a uniform orientation, indicates the molecules in domains I and III adhere to the same epitaxy registry with respect to the graphite lattice. The white dashed line also indicates a clear shift between the two domains. Even more intriguing, since the adsorption of BPT on HOPG surface breaks the mirror plane of the molecular dimer, chiral packing structures are observed in the SAMs of BPT. High-resolution STM image of the domain boundary, as depicted in Figure 2e,shows that the domain II is in fact a mirror domain of I and III. The boundaries of three domains are marked by white arrows. Molecular schemes in red and green colors have been


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superimposed to the STM image for better visualization of molecular arrangement. In the middle of the two domain boundaries (domain-II), the dimers are highlighted as green. The dimers in “domain-I” and “domain-III” are colored in red. We found that those dimers colored in red and green are enantiomers with respect to each other. The enantiomeric packing of BPT dimer can be easily recognized from atomic resolution STM images and is more clearly displayed in a structural model (see Figure 2f). Only along the two domain boundaries can we observed two other types of dimers. One is highlighted by a purple dashed ellipse and another one is marked as a white dashed ellipse, respectively. These molecular dimers are connected to each other through Br···Br bonds with slightly head-to-head (white dashed ellipse) and shoulder-to-shoulder (purple dashed ellipse) geometries, which is beneficial to stabilize the domain boundary.

Figure 2. a-c) Three successive STM images showing the growth of domain boundary at the octanoic acid/HOPG interface. The black arrows highlight the sites where noticeable changes happen. d, e) Large-scale and high-resolution STM images of the domain boundary at the


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octanoic acid/HOPG interface. f) Illustration of the mirror dimers.CPK models of BPT are overlaid on the STM image to guide the eye. The tunneling conditions were Iset= 554 pA, Vbias = 390 mV. (a-c) The scale bar is 20 nm.

Non-covalent self-assembly of BPT molecules at the octanoic acid/SLG interface. Due to difference in electronic properties, we hypothesize that BPT may exhibit different assembling behavior on the monolayer graphene surface in comparison with HOPG, leading to different surface self-assemble structure for BPT. As expected, after deposition of a droplet of BPT octanoic acid solution onto SLG surface, BPT self-assembled into a 2D porous honeycomb structure (C-type),which is very similar to the assembly of star-shaped 1,3,5-tris(4iodophenyl)benzene at the 1-phenyloctane/graphite interface under low concentration.54 Representative STM images of porous honeycomb networks are depicted in Figure 3 and Figure S2, Supporting Information. The large-scale STM image shows a highly ordered 2D network comprised of a majority of honeycomb structure on SLG (Figure 3, Figure S3). It is noteworthy that although the CVD-grown SLG covers the whole surface of the copper foil, it still exists various kinds of corrugations on the copper substrate (Figure 3a,such as step edges highlighted by white arrows). The self-assembly observed on SLG in the present experiments differs from that on graphite, where BPT form both densely-packed (A-type) and loosely-packed (B-type) structures. These three structures differ in their packing pattern and their particular packing density (see Table 1). The high-resolution STM image in Figure 3b reveals that the ends of three molecules are joint in a head-to-head manner. The structure is based on a hexagonal lattice with a = b = (1.5 ± 0.2) nm and α = (60 ± 1)°, and contains one BPT molecule per unit cell. We speculate that the honeycomb structure can either stabilized by a triple Br-Br-Br bond (Figure


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4a) orthree Br…H-C bonds (Figure 4b). In Figure 4a, the distance between Br and H is about 3.2 Å, and the distance between two Br atoms is 2.8 Å, falling in the range of halogen-halogen interactions, indicate the molecules are interconnected with each other in a triple Br-Br-Br bond, While in Figure 4b, the distance between Br and H is about 2.4 Å, falls in the range of hydrogen bond, but the Br-Br distance is larger than 4.1 Å, thus the interconnection is dominated by hydrogen bonds. However, density functional theory (DFT) calculations using these configuration as initial geometries result in the same optimized structure as shown in Figure 4c. The DFT calculation indicates that the honeycomb self-assembly of the BPT is stabilized by both the interaction between Br and H and between Br and Br.

Figure 3. a, b) Large-scale and high-resolution STM images of BPTs self-assembled into honeycomb structure at the octanoic acid/SLG interface. CPK models of BPT are overlaid on the STM image to guide the eye. c) Proposed molecular model. The tunneling conditions were Iset= 376 pA, Vbias = 450 mV.


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Figure 4. a) Initial structure with stronger interaction among three Br atoms. b) Initial structure with stronger interaction between Br and H atoms. c) Optimized results using HF method with 631G** basis set, and values in parenthesis were obtained with density functional theory method SVWN function with 3-21G basis set for C, N, and H atoms and 3-21G* basis set for Br atoms. Bond lengths are in angstrom. d) and e) Optimized configuration of BPT adsorbed on graphene and graphite, respectively. To understand the assembling behaviors both molecular dynamics55,56 and DFT simulations can give good insights, in the current work we use DFT simulation to get more insights into the controlling factors on the assembling of BTP on both substrates. First we survey the difference in adsorption energy on grapheme and graphite to understand the substrate effect. For this purpose the single and double layer graphene was used as substrate to mimic graphene and graphite and one BTP molecule was put on top and allowed to relax. The calculation results showed that all the most stable conformations of BPT are obtained with bromine atom above the centre of a six-


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carbon ring of the graphene or first layer of graphite (shown in Figure 4d and 4e) due to the polarization. The π -π stacking interaction play a decisive role for the BPT adsorbed on the graphene or graphite. The adsorption energy difference is minor (2.31 eV on planar graphene vs. 2.28 eV on graphite) which indicates that the difference in adsorption energy is not decisive in leading to the different packing.

Figure 5. Optimized model of densely-packed (a), loosely-packed (b) and the honeycomb network (c) using DFT calculations performed with SVWN function. The adsorption energy obtained from the simulation is listed below the image. Further simulations with extended model for the three structures (Figure 5) are done with SVWN function with 3-21G basis set for C, N, and H atoms and 3-21G* basis set for Br atoms. In these models two intact BTPs and two with one 4-bromophenyl group omitted are included for the close packed and honeycomb patterns, while in the loose packed pattern two coadsorbed octanoic acid molecules are also considered. The adsorption energies are estimated with Eads = Etotal-Egraphene-2*EA-2*EB, where Etotal, Egraphene, EA and EB are the energy of the total system, graphene, BTP and BTP with one 4-bromophenyl group omitted. These results indicate the stability of the densely-packed and honeycomb pattern are comparable, though in the honeycomb pattern the Br-Br and Br-H interactions are stronger, they are compensated by stronger van der Waals interactions between the molecules in the densely-packed pattern. For loosely-packed pattern, those due to the coadsorption of octanoic acid it results in the biggest adsorption energy,


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if we take into account the difference in packing density between the densely- and looselypacked patterns, their stability should also be comparable, which is also confirmed by the observation of coexistence of these patterns by STM. Thus for the different assembly observed on graphene and graphite, it is not caused by the difference between single layer graphene and graphite, but possibly by the effect of underneath copper substrate.

CONCLUSIONS In summary, we performed a systematic investigation on the substrate effects of the selfassembly of 2,4,6-tris(4-bromophenyl)-1,3,5-triazine by STM at the liquid/solid interface. 2D supramolecular self-assembly structures were realized by adsorption of BPT on HOPG and SLG. Depending on the different substrates used, densely-packed and loosely-packed structures on HOPG and a porous honeycomb network on SLG were revealed by means of in-situ STM, respectively. The two kinds of structures with different packing density on HOPG are both stabilized by Br···H bindings, halogen synthons and van der Waals interaction between neighboring molecules. In addition, we found two other types of dimers in the domain boundaries. One was connected to each other with nearly head-to-head and another one was shoulder-to-shoulder geometries, respectively. Interestingly, we have successfully captured the chiral packing structures at the domain boundary owing to the adsorption of BPT breaks the symmetry of BPT. On SLG, STM results reveal that BPT can self-assemble into porous honeycomb networks predominantly and a few close-packed structures.DFT simulations indicate the porous honeycomb structure was stabilized by bothBr…H-Cand Br-Br-Br bonds and strong molecule-


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substrate interactions together, and the substrate effect might be caused by the copper substrate underneath the single layer graphene rather than the difference between graphene and graphite.

ASSOCIATED CONTENT Large-scale STM images of assembly of BPT molecules on HOPG and SLG obtained at the gas/solid interface. The Supporting Information is available free of charge on the ACS Publications website at DOI: 10.1021/acs.jpcc.0000000.

AUTHOR INFORMATION Corresponding Author *E-mail: [email protected]. Author Contributions The manuscript was written through contributions of all authors. All authors have given approval to the final version of the manuscript. Notes The authors declare no competing financial interest.


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ACKNOWLEDGMENTS This work was supported by the National Science Foundation of China (21572157, 51633006), the Ministry of Science and Technology of China (Grants 2016YFB0401100).

REFERENCES (1) Whitesides, G. M.; Mathias, J. P.; Seto, C. T. Molecular Self-Assembly and Nanochemistry-A Chemical Strategy for the Synthesis of Nanostructures. Science 1991, 254, 1312-1319. (2) Whitesides, G. M.; Grzybowski, B. Self-Assembly at All Scales. Science 2002, 295, 24182421. (3) Barth, J. V.; Costantini, G.; Kern, K. Engineering Atomic and Molecular Nanostructures at Surfaces. Nature 2005, 437, 671-679. (4) Mali, K. S.; Adisoejoso, J.; Ghijsens, E.; De Cat, I.; De Feyter, S. Exploring the Complexity of Supramolecular Interactions for Patterning at the Liquid-Solid Interface. Acc. Chem. Res. 2012, 45, 1309-1320. (5) Rosei, F. Nanostructured Surfaces: Challenges and Frontiers in Nanotechnology. J. Phys. Condens. Matter. 2004, 16, S1373-S1436. (6) Elemans, J. A.; Lei S.; De Feyter S. Molecular and Supramolecular Networks on Surfaces: from Two-Dimensional Crystal Engineering to Reactivity. Angew. Chem., Int. Ed. 2009, 48, 7298-7332. (7) Mourran, A.; Ziener, U.; Möller, M.; Suarez, M.; Lehn, J. M. Homo- and Heteroassemblies of Lactim/Lactam Recognition Patterns on Highly Ordered Pyrolytic Graphite: An STM Investigation. Langmuir 2006, 22, 7579-7586.


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(8) Mamdouh, W.; Uji-I, H.; Ladislaw, J. S.; Dulcey, A. E.; Percec, V.; De Schryver, F. C.; De Feyter, S. Solvent Controlled Self-Assembly at the Liquid-Solid Interface Revealed by STM. J. Am. Chem. Soc. 2006, 128, 317-325. (9) Zhang, X.; Chen, Q.; Deng, G. J.; Fan, Q. H.; Wan, L. J. Structural Diversity of a Monodendron Molecule Self-Assembly in Different Solvents Investigated by Scanning Tunneling Microscopy: From Dispersant to Counterpart. J. Phys. Chem. C 2009, 113, 1619316198. (10) Miao, K.; Hu, Y.; Zha, B.; Xu, L.; Miao, X. R.; Deng, W. L. Hydroxyl versus Carboxyl Substituent: Effects of Competitive and Cooperative Multiple Hydrogen Bonds on Concentration-Controlled Self-Assembly. J. Phys. Chem. C 2016, 120, 14187-14197. (11) Dai, H.; Yi, W.; Deng, K.; Wang, H.; Zeng, Q. Formation of Coronene Clusters in Concentration and Temperature Controlled Two-Dimensional Porous Network. ACS Appl Mater Interfaces 2016, 8, 21095-21100. (12) Blunt, M. O.; Adisoejoso, J.; Tahara, K.; Katayama, K.; Auweraer, M. V. D.; Tobe, Y.; De Feyter, S. Temperature-Induced Structural Phase Transitions in a Two-Dimensional SelfAssembled Network. J. Am. Chem. Soc. 2013, 135, 12068-12075. (13) Gutzler, R.; Sirtl, T.; Dienstmaier, J. F.; Mahata, K.; Heckl, W. M.; Schmittel, M.; Lackinger, M. Reversible Phase Transitions in Self-Assembled Monolayers at the Liquid-Solid Interface: Temperature-Controlled Opening and Closing of Nanopores. J. Am. Chem. Soc. 2010, 132, 5084-5090. (14) Sicot, M.; Tristant, D.; Gerber, I. C.; Kierren, B.; Chérioux, F.; Fagot-Revurat, Y.; Moreau, L.; Granet, J.; Malterre, D. Polymorphism of Two-Dimensional Halogen Bonded


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Supramolecular Networks on a Graphene/Iridium(111) Surface. J. Phys. Chem. C 2017, 121, 2201-2210. (15) Sykes, E. C.; Han, P.; Kandel, S. A.; Kelly, K. F.; McCarty, G. S.; Weiss, P. S. Substrate-Mediated Interactions and Intermolecular Forces between Molecules Adsorbed on Surfaces. Acc. Chem. Res. 2003, 36, 945-953. (16) Eremtchenko, M.; Schaefer, J. A.; Tautz, F. S. Understanding and Tuning the Epitaxy of Large Aromatic Adsorbates by Molecular Design. Nature 2003, 425, 602-605. (17) Kong, X.H.; Deng, K.; Yang, Y.L.; Zeng Q.D.; Wang, C. Effect of Thermal Annealing on Hydrogen Bond Configurations of Host Lattice Revealed in VOPc/TCDB Host-Guest Architectures. J. Phys. Chem. C 2007, 111, 9235-9239. (18) Dmitriev, A.; Spillmann, H.; Lin, N.; Barth J. V.; Kern, K. Modular Assembly of TwoDimensional Metal-Organic Coordination Networks at a Metal Surface. Angew. Chem., Int. Ed. 2003, 42, 2670-2673. (19) Tahara, K.; Furukawa, S.; Uji-i, H.; Uchino, T.; Ichikawa, T.; Zhang, J.; Mamdouh, W.; Sonoda, M.; De Schryver, F. C.; De Feyter, S.; Tobe, Y. Two-Dimensional Porous Molecular Networks of Dehydrobenzo[12]Annulene Derivatives via Alkyl Chain Interdigitation. J. Am. Chem. Soc. 2006, 128, 16613-16625. (20) Chen, Q.; Yan, H.; Yan, C.; Pan, G.; Wan, L.; Wen, G.; Zhang, D. STM Investigation of the Dependence of Alkane and Alkane (C18H38, C19H40) Derivatives Self-Assembly on Molecular Chemical Structure on HOPG Surface. Surf. Sci. 2008, 602, 1256-1266. (21) Dickerson, P. N.; Hibberd, A. M.; Oncel, N.; Bernasek, S. L. Hydrogen-Bonding versus van der Waals Interactions in Self-Assembled Monolayers of Substituted Isophthalic Acids. Langmuir 2010, 26, 18155-18161.


18

Page 19 of 24 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


(22) Cnossen, A.; Pijper, D.; Kudernac, T.; Pollard, M. M.; Katsonis, N.; Feringa, B. L.; A Trimer of Ultrafast Nanomotors: Synthesis, Photochemistry and Self-Assembly on Graphite. Chem. -Eur. J. 2009, 15, 2768-2772. (23) Grimme, S.; Do Special Noncovalent π-π Stacking Interactions Really Exist? Angew. Chem., Int. Ed. 2008, 47, 3430-3434. (24) Priimagi, A.; Cavallo, G.; Metrangolo, P.; Resnati, G. The Halogen Bond in the Design of Functional Supramolecular Materials: Recent Advances. Acc. Chem. Res. 2013, 46, 26862695. (25) Metrangolo, P.; Meyer, F.; Pilati, T.; Resnati, G.; Terraneo, G. Halogen Bonding in Supramolecular Chemistry. Angew. Chem., Int. Ed. 2008, 47, 6114-6127. (26) Meazza, L.; Foster, J. A.; Fucke, K.; Metrangolo, P.; Resnati, G.; Steed, J. W. HalogenBonding-Triggered Supramolecular Gel Formation. Nat. Chem. 2013, 5, 42-47. (27) Bui, T. T. T.; Dahaoui, S.; Lecomte, C.; Desiraju, G. R.; Espinosa, E. The Nature of Halogen···Halogen Interactions: A Model Derived from Experimental Charge-Density Analysis. Angew. Chem., Int. Ed. 2009, 48, 3838-3841. (28) Reddy, C. M.; Kirchner, M. T.; Gundakaram, R. C.; Padmanabhan, K. A.; Desiraju, G. R. Isostructurality, Polymorphism and Mechanical Properties of Some Hexahalogenates Benzenes: The Nature of Halogen···Halogen Interactions. Chem.-Eur. J. 2006, 12, 2222-2234. (29) Lu, Y. X.; Zhang, S. Z.; Peng, C. J.; Liu, H. L. Interplay between Halogen and Hydrogen Bonds in 2D Self-Assembly on the Gold Surface: A First-Principles Investigation. J. Phys. Chem. C 2017, 121, 24707-24720.


19


Page 20 of 24

(30) Gatti, R.; Macleod, J. M.; Liptonduffin, J. A.; Moiseev, A. G.; Perepichka, D. F.; Rosei, F. Substrate, Molecular Structure, and Solvent Effects in 2D Self-Assembly via Hydrogen and Halogen Bonding. J. Phys. Chem. C 2014, 118, 25505-25516. (31) Gilday, L. C.; Robinson, S. W.; Barendt, T. A.; Langton, M. J.; Mullaney, B. R.; Beer, P. D. Halogen Bonding in Supramolecular Chemistry. Chem. Rev.2015, 115, 7118-7195. (32) Awwadi, F. F.; Willett, R. D.; Peterson K. A.; Twamley, B. The Nature of Halogen···Halogen Synthons: Crystallographic and Theoretical Studies. Chem.-Eur. J.2006, 12, 8952-8960. (33) Legon, A. C. The Halogen Bond: an Interim Perspective. Phys. Chem. Chem. Phys.2010, 12, 7736-7747. (34) Chen, Q.; Chen, T.; Zhang, X.; Wan, L.J.; Liu, H. B.; Li Y.L.; Stang, P.Two-Dimensional OPV4 Self-Assembly and Its Coadsorption with Alkyl Bromide: From Helix to Lamellar. Chem. Commun.2009, 25, 3765-3767. (35) Chen, Q.; Chen, T.; Wang, D.; Liu, H.B.; Li Y.L.; Wan L.J. Structure and Structural Transition of Chiral Domains in Oligo(p-Phenylenevinylene) Assembly Investigated by Scanning Tunneling Microscopy. Proc. Natl. Acad. Sci. USA.2010, 107, 2769-2774. (36) Gutzler, R.; Ivasenko, O.; Fu, C.; Brusso, J. L.; Rosei F.; Perepichka, D. F. Halogen Bonds as Stabilizing Interactions in a Chiral Self-Assembled Molecular Monolayer. Chem. Commun.2011, 47, 9453-9455. (37) Yoon, J. K.; Son, W.J.; Chung, K.H.; Kim, H.; Han, S.; Kahng, S.J. Visualizing Halogen Bonds in Planar Supramolecular Systems. J. Phys. Chem. C2011, 115, 2297-2301.


20

Page 21 of 24 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


(38) Chung, K.H.; Park, J.; Kim, K. Y.; Yoon, J. K.; Kim, H.; Han S.; Kahng, S.J.Polymorphic Porous Supramolecular Networks Mediated by Halogen Bonds on Ag(111). Chem. Commun. 2011, 47, 11492-11494. (39) Gutzler, R.; Fu, C.; Dadvand, A.; Hua, Y.; MacLeod, J. M.; Rosei, F.; Perepichka, D. F. Halogen

Bonds

in

2D Supramolecular Self-Assembly of Organic Semiconductors.

Nanoscale2012, 4, 5965-5971. (40) Tomović, Z.; van Dongen, J.; George, S. J.; Xu, H.; Pisula, W.; Leclère, P.; Smulders, M. M.; De Feyter, S.; Meijer, E. W.; Schenning, A. P. Star-Shaped Oligo(p-Phenylenevinylene) Substituted Hexaarylbenzene: Purity, Stability, and Chiral Self-Assembly. J. Am. Chem. Soc. 2007, 129, 16190-16196. (41) Ruben, M.; Payer, D.; Landa, A.; Comisso, A.; Gattinoni, C.; Lin, N.; Collin, J. P.; Sauvage, J. P.; De Vita, A.; Kern, K. 2D Supramolecular Assemblies of Benzene-1,3,5-triyltribenzoic Acid: Temperature-Induced Phase Transformations and Hierarchical Organization with Macrocyclic Molecules.J. Am. Chem. Soc. 2007, 128, 15644-15651. (42) Ciesielski, A.; Szabelski, P. J.; Rżysko, W.; Cadeddu, A.; Cook, T. R.; Stang, P. J.; Samorì, P. Concentration-Dependent Supramolecular Engineering of Hydrogen-Bonded Nanostructures at Surfaces: Predicting Self-Assembly in 2D. J. Am. Chem. Soc.2013, 135, 69426950. (43) Silly, F. Selecting Two-Dimensional Halogen-Halogen Bonded Self-Assembled 1,3,5Tris(4-iodophenyl)benzene Porous Nanoarchitectures at the Solid-Liquid Interface. J. Phys. Chem. C2013, 117, 20244-20249.


21


Page 22 of 24

(44) Vives, G.; Carella, A.; Launay, J.P.; Rapenne, G. A Star-Shaped Ruthenium Complex with Five Ferrocenyl-Terminated Arms Bridged by trans-Platinum Fragments. Chem. Commun. 2006, 21, 2283-2285. (45) Silly, F. Two-Dimensional 1,3,5-Tris(4-carboxyphenyl)benzene Self-Assembly at the 1Phenyloctane/Graphite Interface Revisited. J. Phys. Chem. C2012, 116, 10029-10032. (46) Gutzler, R.; Walch, H.; Eder, G.; Kloft, S.; Heckl, W. M.; Lackinger, M. Surface Mediated Synthesis of 2D Covalent Organic Frameworks: 1,3,5-Tris(4-bromophenyl)benzene on Graphite(001), Cu(111), and Ag(110). Chem. Commun.2009, 29, 4456-4458. (47) Blunt, M. O.; Russell, J. C.; Champness, N. R.; Beton, P. H. Templating Molecular Adsorption Using a Covalent Organic Framework. Chem. Commun.2010, 46, 7157-7159. (48) Russell, J. C.; Blunt, M. O.; Garfitt, J. M.; Scurr, D. J.; Alexander, M.; Champness, N. R.; Beton, P. H. Dimerization of Tri(4-bromophenyl)benzene by Aryl-Aryl Coupling from Solution on a Gold Surface. J. Am. Chem. Soc. 2011, 133, 4220-4223. (49) Gatti, R.; Macleod, J. M.; Liptonduffin, J. A.; Moiseev, A. G.; Perepichka, D. F.; Rosei, F. Substrate, Molecular Structure, and Solvent Effects in 2D Self-Assembly via Hydrogen and Halogen Bonding. J. Phys. Chem. C2014, 118, 25505-25516. (50)Silly, F. Two-Dimensional Self-Assembly of 2,4,6-Tris(4',4'',4'''-trimethylphenyl)-1,3,5Triazine Star-Shaped Molecules: Nanoarchitecture Structure and Domain Boundaries. J. Phys. Chem. C 2014, 118, 11975-11979. (51) Sirtl, T.; Schlögl, S.; Rastgoo-Lahrood, A.; Jelic, J.; Neogi, S.; Schmittel, M.; Heckl, W. M.; Reuter, K.; Lackinger, M. Control of Intermolecular Bonds by Deposition Rates at Room Temperature: Hydrogen Bonds versus Metal Coordination in Trinitrile Monolayers. J. Am. Chem. Soc.2013, 135, 691-695.


22

Page 23 of 24 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


(52) Baris, B.; Luzet, V.; Duverger, E.; Sonnet, P.; Palmino, F.; Chérioux, F. Robust and Open Tailored Supramolecular Networks Controlled by the Template Effect of a Silicon Surface. Angew. Chem., Int. Ed. 2011, 50, 4094-4098. (53) Silly, F.; Viala, C.; Bonvoisin J. Two-Dimensional Halogen-Bonded Porous SelfAssembled Nanoarchitectures of Copper β‑Diketonato Complexes, J. Phys. Chem. C2018, DOI: 10.1021/acs.jpcc.8b01390. (54) Silly, F. Concentration-Dependent Two-Dimensional Halogen-Bonded Self-Assemblyof 1,3,5-Tris(4-iodophenyl)benzene Molecules at theSolid−Liquid Interface. J. Phys. Chem. C2017, 121, 10413−10418. (55) Mukhopadhyay, T. K.; Datta, A. Ordering and Dynamics for the Formation of TwoDimensional Molecular Crystals on Black Phosphorene,J. Phys. Chem. C2017, 121,10210-10223. (56)Mukhopadhyay, T. K.; Datta, A. Deciphering the Role of Solvents in the Liquid Phase Exfoliation of Hexagonal Boron Nitride: A Molecular Dynamics Simulation Study,J. Phys. Chem. C2017, 121, 811-822.


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Substrate Effects in the Supramolecular Self-Assembly of 2,4,6-Tris(4

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