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Sahu R, Yamijala SSRKC, Rao KV, Reddy SK. Dispersion-Driven Cooperativity in Alkyl Perylene Diimide Oligomers: Insights from Density Functional Theory. Chemphyschem 2024; 25:e202400235. [PMID: 38807431 DOI: 10.1002/cphc.202400235] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2024] [Revised: 05/16/2024] [Accepted: 05/28/2024] [Indexed: 05/30/2024]
Abstract
The cooperative mechanism is of paramount importance in the synthesis of supramolecular polymers with desired characteristics, including molecular mass, polydispersity, and morphology. It is primarily driven by the presence of intermolecular interactions, which encompass strong hydrogen bonding, metal-ligand interactions, and dipole-dipole interactions. In this study, we utilize density functional theory and energy decomposition analysis to investigate the cooperative behavior of perylene diimide (PDI) oligomers with alkyl chains at their imide positions, which lack the previously mentioned interactions. Our systematic examination reveals that dispersion interactions originating from the alkyl side-chain substituents play an important role in promoting cooperativity within these PDIs. This influence becomes even more pronounced for alkyl chain lengths beyond hexyl groups. The energy decomposition analysis reveals that the delicate balance between dispersion energy and Pauli repulsion energy is the key driver of cooperative behavior in PDIs. Additionally, we have developed a mathematical model capable of predicting the saturated binding energies for PDI oligomers of varying sizes and alkyl chain lengths. Overall, our findings emphasize the previously undervalued significance of dispersion forces in cooperative supramolecular polymerization, enhancing our overall understanding of the cooperative mechanism.
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Affiliation(s)
- Rahul Sahu
- Centre for Computational and Data Sciences, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal, Pin, 721302, India
| | - Sharma S R K C Yamijala
- Department of Chemistry, Centre for Atomistic Modelling and Materials Design, Centre for Quantum Information, Communication, and Computing, Centre for Molecular Materials and Functions, Indian Institute of Technology Madras, Chennai, 600036, Tamil Nadu, Pin, India
- Centre for Atomistic Modelling and Materials Design, Indian Institute of Technology Madras, Chennai, Tamil Nadu, Pin, 600036, India
- Centre for Quantum Information, Communication, and Computing, Indian Institute of Technology Madras, Chennai, Tamil Nadu, Pin, 600036, India
- Centre for Molecular Materials and Functions, Indian Institute of Technology Madras, Chennai, Tamil Nadu, Pin, 600036, India
| | - Kotagiri Venkata Rao
- Department of Chemistry, Indian Institute of Technology Hyderabad, Kandi, Sangareddy, Telangana, Pin, 502285, India
| | - Sandeep K Reddy
- Centre for Computational and Data Sciences, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal, Pin, 721302, India
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2
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Li Y, Castillo HD, Dobscha JR, Morgan AR, Tait SL, Flood AH. Breaking Radial Dipole Symmetry in Planar Macrocycles Modulates Edge-to-Edge Packing and Disrupts Cofacial Stacking. Chemistry 2024; 30:e202302946. [PMID: 37950681 DOI: 10.1002/chem.202302946] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2023] [Revised: 11/07/2023] [Accepted: 11/08/2023] [Indexed: 11/13/2023]
Abstract
Dipolar interactions are ever-present in supramolecular architectures, though their impact is typically revealed by making dipoles stronger. While it is also possible to assess the role of dipoles by altering their orientations by using synthetic design, doing so without altering the molecular shape is not straightforward. We have now done this by flipping one triazole unit in a rigid macrocycle, tricarb. The macrocycle is composed of three carbazoles (2 Debye) and three triazoles (5 Debye) defining an array of dipoles aligned radially but organized alternately in and out. These dipoles are believed to dictate edge-to-edge tiling and face-to-face stacking. We modified our synthesis to prepare isosteric macrocycles with the orientation of one triazole dipole rotated 40°. The new dipole orientation guides edge-to-edge contacts to reorder the stability of two surface-bound 2D polymorphs. The impact on dipole-enhanced π stacking, however, was unexpected. Our stacking model identified an unchanged set of short-range (3.4 Å) anti-parallel dipole contacts. Despite this situation, the reduction in self-association was attributed to long-range (~6.4 Å) dipolar repulsions between π-stacked macrocycles. This work highlights our ability to control the build-up and symmetry of macrocyclic skeletons by synthetic design, and the work needed to further our understanding of how dipoles control self-assembly.
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Affiliation(s)
- Yan Li
- Department of Chemistry, Indiana University, 800 E. Kirkwood Avenue, Bloomington, IN, 47405, USA
| | - Henry D Castillo
- Department of Chemistry, Indiana University, 800 E. Kirkwood Avenue, Bloomington, IN, 47405, USA
| | - James R Dobscha
- Department of Chemistry, Indiana University, 800 E. Kirkwood Avenue, Bloomington, IN, 47405, USA
| | - Amanda R Morgan
- Department of Chemistry, Indiana University, 800 E. Kirkwood Avenue, Bloomington, IN, 47405, USA
| | - Steven L Tait
- Department of Chemistry, Indiana University, 800 E. Kirkwood Avenue, Bloomington, IN, 47405, USA
| | - Amar H Flood
- Department of Chemistry, Indiana University, 800 E. Kirkwood Avenue, Bloomington, IN, 47405, USA
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3
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Pinjari A, Saraf D, Sengupta D. Molecular mechanisms underlying nanowire formation in pristine phthalocyanine. Phys Chem Chem Phys 2023; 25:30259-30268. [PMID: 37927067 DOI: 10.1039/d3cp03512c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2023]
Abstract
Understanding the molecular processes of nanowire self-assembly is crucial for designing and controlling nanoscale structures that could lead to breakthroughs in functional materials. In this work, we focus on pristine phthalocyanines as a representative example of mesogenic supramolecular assemblies and have analyzed the formation of nanowires using classical molecular dynamics simulations. In the simulations, the molecules spontaneously form multi-columnar structures resembling supramolecular polymers that subsequently grow into more ordered aggregates. These self-assemblies are concentration dependent, leading to the formation of multi-columnar, dynamic aggregates at higher concentrations and nanowires at lower concentrations. The multi-columnar assemblies on a whole are more disordered than the nanowires, but have locally ordered domains of parallel facing molecules that can fluctuate while maintaining their overall shape. The nanowire formation at lower concentrations involves the initial interaction and clustering of randomly oriented phthalocyanine molecules, followed by the merging of small clusters into elongated segments and the eventual formation of a stable nanowire. We observe three main conformers in these self-assemblies, the parallel, T-shaped and edge-to-edge stacking of the phthalocyanine dimers. We calculate the underlying free energy landscape and show that the parallel conformers form the most stable configuration which is followed by the T-shaped and edge-to-edge dimer configurations. The findings provide insights into the mechanisms and pathways of nanowire formation and a step towards the understanding of self-assembly processes in supramolecular mesogens.
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Affiliation(s)
- Aadil Pinjari
- CSIR-National Chemical Laboratory, Dr Homi Bhabha Road, Pune 411 008, India.
| | - Deepashri Saraf
- CSIR-National Chemical Laboratory, Dr Homi Bhabha Road, Pune 411 008, India.
| | - Durba Sengupta
- CSIR-National Chemical Laboratory, Dr Homi Bhabha Road, Pune 411 008, India.
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh, 201 002, India
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Cooperative Supramolecular Polymerization of Propeller-Shaped Triphenylamine Cyanostilbenes for Explosive Detection. CHINESE JOURNAL OF POLYMER SCIENCE 2023. [DOI: 10.1007/s10118-023-2917-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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5
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Ślęczkowski ML, Mabesoone MFJ, Preuss MD, Post Y, Palmans ARA, Meijer EW. Helical bias in supramolecular polymers accounts for different stabilities of kinetically trapped states. JOURNAL OF POLYMER SCIENCE 2022. [DOI: 10.1002/pol.20220036] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Marcin L. Ślęczkowski
- Institute for Complex Molecular Systems Eindhoven University of Technology Eindhoven The Netherlands
- Laboratory of Macromolecular and Organic Chemistry Eindhoven University of Technology Eindhoven The Netherlands
| | - Mathijs F. J. Mabesoone
- Institute for Complex Molecular Systems Eindhoven University of Technology Eindhoven The Netherlands
- Laboratory of Macromolecular and Organic Chemistry Eindhoven University of Technology Eindhoven The Netherlands
- Institute of Microbiology Eidgenössische Technische Hochschule Zürich Zürich Switzerland
| | - Marco D. Preuss
- Institute for Complex Molecular Systems Eindhoven University of Technology Eindhoven The Netherlands
- Laboratory of Macromolecular and Organic Chemistry Eindhoven University of Technology Eindhoven The Netherlands
| | - Yorick Post
- Institute for Complex Molecular Systems Eindhoven University of Technology Eindhoven The Netherlands
| | - Anja R. A. Palmans
- Institute for Complex Molecular Systems Eindhoven University of Technology Eindhoven The Netherlands
- Laboratory of Macromolecular and Organic Chemistry Eindhoven University of Technology Eindhoven The Netherlands
| | - E. W. Meijer
- Institute for Complex Molecular Systems Eindhoven University of Technology Eindhoven The Netherlands
- Laboratory of Macromolecular and Organic Chemistry Eindhoven University of Technology Eindhoven The Netherlands
- School of Chemistry and the UNSW RNA Institute University of New South Wales Sydney Australia
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Koch M, Saphiannikova M, Guskova O. Columnar Aggregates of Azobenzene Stars: Exploring Intermolecular Interactions, Structure, and Stability in Atomistic Simulations. Molecules 2021; 26:7598. [PMID: 34946680 PMCID: PMC8703797 DOI: 10.3390/molecules26247598] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 12/09/2021] [Accepted: 12/10/2021] [Indexed: 11/16/2022] Open
Abstract
We present a simulation study of supramolecular aggregates formed by three-arm azobenzene (Azo) stars with a benzene-1,3,5-tricarboxamide (BTA) core in water. Previous experimental works by other research groups demonstrate that such Azo stars assemble into needle-like structures with light-responsive properties. Disregarding the response to light, we intend to characterize the equilibrium state of this system on the molecular scale. In particular, we aim to develop a thorough understanding of the binding mechanism between the molecules and analyze the structural properties of columnar stacks of Azo stars. Our study employs fully atomistic molecular dynamics (MD) simulations to model pre-assembled aggregates with various sizes and arrangements in water. In our detailed approach, we decompose the binding energies of the aggregates into the contributions due to the different types of non-covalent interactions and the contributions of the functional groups in the Azo stars. Initially, we investigate the origin and strength of the non-covalent interactions within a stacked dimer. Based on these findings, three arrangements of longer columnar stacks are prepared and equilibrated. We confirm that the binding energies of the stacks are mainly composed of π-π interactions between the conjugated parts of the molecules and hydrogen bonds formed between the stacked BTA cores. Our study quantifies the strength of these interactions and shows that the π-π interactions, especially between the Azo moieties, dominate the binding energies. We clarify that hydrogen bonds, which are predominant in BTA stacks, have only secondary energetic contributions in stacks of Azo stars but remain necessary stabilizers. Both types of interactions, π-π stacking and H-bonds, are required to maintain the columnar arrangement of the aggregates.
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Affiliation(s)
- Markus Koch
- Institute Theory of Polymers, Leibniz Institute of Polymer Research Dresden, Hohe Str. 6, 01069 Dresden, Germany;
| | - Marina Saphiannikova
- Institute Theory of Polymers, Leibniz Institute of Polymer Research Dresden, Hohe Str. 6, 01069 Dresden, Germany;
- Dresden Center for Computational Materials Science (DCMS), Technische Universität Dresden, 01062 Dresden, Germany
| | - Olga Guskova
- Institute Theory of Polymers, Leibniz Institute of Polymer Research Dresden, Hohe Str. 6, 01069 Dresden, Germany;
- Dresden Center for Computational Materials Science (DCMS), Technische Universität Dresden, 01062 Dresden, Germany
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Henderson WR, Liu G, Abboud KA, Castellano RK. Tuning Supramolecular Polymer Assembly through Stereoelectronic Interactions. J Am Chem Soc 2021; 143:12688-12698. [PMID: 34346675 DOI: 10.1021/jacs.1c05522] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The supramolecular polymerization of 2,11-dithia[3.3]paracyclophanes through self-complementary intermolecular and transannular amide hydrogen bonding is presented. An n → π* interaction between the amide hydrogen bonding units and the central bridging atom results from the single-point exchange of a carbon atom for a sulfur atom. This orbital donor-acceptor interaction can be strengthened by oxidizing the sulfide to a sulfone which acts to shorten the donor···acceptor distance and increase orbital overlap. Experimental signatures of the increased n → π* interaction include larger isodesmic polymerization elongation constants in solution, changes in characteristic bond stretching frequencies, and geometric/structural changes evaluated by X-ray crystallography. The experimental data are supported by extensive computational investigations of both assembling and nonassembling 2,11-dithia[3.3]paracyclophanes as well as a rationally designed model system to confirm the role of stereoelectronic effects on supramolecular polymer assembly.
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Affiliation(s)
- Will R Henderson
- George & Josephine Butler Polymer Research Laboratory, Center for Macromolecular Science & Engineering, Department of Chemistry, University of Florida, P.O. Box 117200 Gainesville, Florida 32611-7200, United States
| | - Guancen Liu
- George & Josephine Butler Polymer Research Laboratory, Center for Macromolecular Science & Engineering, Department of Chemistry, University of Florida, P.O. Box 117200 Gainesville, Florida 32611-7200, United States
| | - Khalil A Abboud
- George & Josephine Butler Polymer Research Laboratory, Center for Macromolecular Science & Engineering, Department of Chemistry, University of Florida, P.O. Box 117200 Gainesville, Florida 32611-7200, United States
| | - Ronald K Castellano
- George & Josephine Butler Polymer Research Laboratory, Center for Macromolecular Science & Engineering, Department of Chemistry, University of Florida, P.O. Box 117200 Gainesville, Florida 32611-7200, United States
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8
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Korlepara DB, Balasubramanian S. Dipolar relaxation in thin films of supramolecular stacks of benzenecarboxamides and insights to enhance their ferroelectric characteristics. Phys Chem Chem Phys 2021; 23:3152-3159. [PMID: 33496287 DOI: 10.1039/d0cp05239f] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The relationship between molecular structure and ferroelectric behaviour of thin films is explored in an all-organic supramolecular polymer material based on benzenecarboxamides, using atomistic molecular dynamics simulations. While increasing the number of amide groups around the phenyl core increases the dipole density of a molecule, increasing the length of the corresponding alkyl groups decreases the same. The interplay between these two contributions displays a rich behaviour on key material characteristics, in particular, the polarisation retention time. The latter is shown to be inversely proportional to the alkyl chain length, a consequence of weaker interactions between macrodipoles of stacks. Polarisation retention time was observed to be the highest in a molecule with five amide groups around the aromatic phenyl core which is explained as due to the large barrier for amide group rotation, which is one of the crucial channels for dipolar relaxation. Simulations also demonstrate that the barrier, however, does not affect the switchability of polarization, upon field reversal.
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Affiliation(s)
- Divya B Korlepara
- Chemistry and Physics of Materials Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur P. O., Bangalore 560064, India.
| | - Sundaram Balasubramanian
- Chemistry and Physics of Materials Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur P. O., Bangalore 560064, India.
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9
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Henderson WR, Kumar A, Abboud KA, Castellano RK. Influence of Amide Connectivity on the Hydrogen‐Bond‐Directed Self‐Assembly of [n.n]Paracyclophanes. Chemistry 2020; 26:17588-17597. [DOI: 10.1002/chem.202003909] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Revised: 09/22/2020] [Indexed: 02/02/2023]
Affiliation(s)
- Will R. Henderson
- George & Josephine Butler Polymer Research Laboratory Center for Macromolecular Science & Engineering Department of Chemistry University of Florida, P.O. Box 117200 Gainesville Florida 32611 USA
| | - Ajeet Kumar
- George & Josephine Butler Polymer Research Laboratory Center for Macromolecular Science & Engineering Department of Chemistry University of Florida, P.O. Box 117200 Gainesville Florida 32611 USA
| | - Khalil A. Abboud
- George & Josephine Butler Polymer Research Laboratory Center for Macromolecular Science & Engineering Department of Chemistry University of Florida, P.O. Box 117200 Gainesville Florida 32611 USA
| | - Ronald K. Castellano
- George & Josephine Butler Polymer Research Laboratory Center for Macromolecular Science & Engineering Department of Chemistry University of Florida, P.O. Box 117200 Gainesville Florida 32611 USA
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10
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Henderson WR, Castellano RK. Supramolecular polymerization of chiral molecules devoid of chiral centers. POLYM INT 2020. [DOI: 10.1002/pi.6111] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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11
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Henderson WR, Zhu Y, Fagnani DE, Liu G, Abboud KA, Castellano RK. Self-Assembling [n.n]Paracyclophanes: A Structure–Property Relationship Study. J Org Chem 2019; 85:1158-1167. [DOI: 10.1021/acs.joc.9b03120] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Will R. Henderson
- Department of Chemistry, University of Florida, PO Box 117200, Gainesville, Florida 32611-7200, United States
| | - Yu Zhu
- Department of Chemistry, University of Florida, PO Box 117200, Gainesville, Florida 32611-7200, United States
| | - Danielle E. Fagnani
- Department of Chemistry, University of Florida, PO Box 117200, Gainesville, Florida 32611-7200, United States
| | - Guancen Liu
- Department of Chemistry, University of Florida, PO Box 117200, Gainesville, Florida 32611-7200, United States
| | - Khalil A. Abboud
- Department of Chemistry, University of Florida, PO Box 117200, Gainesville, Florida 32611-7200, United States
| | - Ronald K. Castellano
- Department of Chemistry, University of Florida, PO Box 117200, Gainesville, Florida 32611-7200, United States
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Savchenko V, Koch M, Pavlov AS, Saphiannikova M, Guskova O. Stacks of Azobenzene Stars: Self-Assembly Scenario and Stabilising Forces Quantified in Computer Modelling. Molecules 2019; 24:E4387. [PMID: 31801297 PMCID: PMC6930662 DOI: 10.3390/molecules24234387] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Revised: 11/25/2019] [Accepted: 11/28/2019] [Indexed: 12/27/2022] Open
Abstract
In this paper, the columnar supramolecular aggregates of photosensitive star-shaped azobenzenes with benzene-1,3,5-tricarboxamide core and azobenzene arms are analyzed theoretically by applying a combination of computer simulation techniques. Without a light stimulus, the azobenzene arms adopt the trans-state and build one-dimensional columns of stacked molecules during the first stage of the noncovalent association. These columnar aggregates represent the structural elements of more complex experimentally observed morphologies-fibers, spheres, gels, and others. Here, we determine the most favorable mutual orientations of the trans-stars in the stack in terms of (i) the π - π distance between the cores lengthwise the aggregate, (ii) the lateral displacements due to slippage and (iii) the rotation promoting the helical twist and chirality of the aggregate. To this end, we calculate the binding energy diagrams using density functional theory. The model predictions are further compared with available experimental data. The intermolecular forces responsible for the stability of the stacks in crystals are quantified using Hirshfeld surface analysis. Finally, to characterize the self-assembly mechanism of the stars in solution, we calculate the hydrogen bond lengths, the normalized dipole moments and the binding energies as functions of the columnar length. For this, molecular dynamics trajectories are analyzed. Finally, we conclude about the cooperative nature of the self-assembly of star-shaped azobenzenes with benzene-1,3,5-tricarboxamide core in aqueous solution.
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Affiliation(s)
- Vladyslav Savchenko
- Dresden Center for Computational Materials Science (DCMS), Technische Universität Dresden, 01062 Dresden, Germany; (V.S.); (M.S.)
- Institute Theory of Polymers, Leibniz Institute of Polymer Research Dresden, Hohe Str. 6, 01069 Dresden, Germany;
| | - Markus Koch
- Institute Theory of Polymers, Leibniz Institute of Polymer Research Dresden, Hohe Str. 6, 01069 Dresden, Germany;
| | - Aleksander S. Pavlov
- Department of Physical Chemistry, Faculty of Chemistry and Technology, Tver State University, Sadovyj per. 35, Tver 170002, Russia;
| | - Marina Saphiannikova
- Dresden Center for Computational Materials Science (DCMS), Technische Universität Dresden, 01062 Dresden, Germany; (V.S.); (M.S.)
- Institute Theory of Polymers, Leibniz Institute of Polymer Research Dresden, Hohe Str. 6, 01069 Dresden, Germany;
| | - Olga Guskova
- Dresden Center for Computational Materials Science (DCMS), Technische Universität Dresden, 01062 Dresden, Germany; (V.S.); (M.S.)
- Institute Theory of Polymers, Leibniz Institute of Polymer Research Dresden, Hohe Str. 6, 01069 Dresden, Germany;
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Koch M, Saphiannikova M, Guskova O. Do Columns of Azobenzene Stars Disassemble under Light Illumination? LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:14659-14669. [PMID: 31627699 DOI: 10.1021/acs.langmuir.9b02960] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The clustering properties of star-shaped molecules comprising three photochromic azobenzene-containing arms are investigated with specific focus on the influence of light on these structures. Previous experimental works report self-assembly of azobenzene stars in aqueous solution into long columnar clusters that are detectable using optical microscopy. These clusters appear to vanish under UV irradiation, which is known to induce trans-to-cis photoisomerization of the azobenzene groups. We have performed MD simulations, density functional theory, and density functional tight binding calculations to determine conformational properties and binding energies of these clusters. Our simulation data suggest that the binding strength of the clusters is large enough to prevent a breaking along their main axis. We conclude that very likely other mechanisms lead to the apparent disappearance of the clusters.
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Affiliation(s)
- Markus Koch
- Institute Theory of Polymers , Leibniz Institute of Polymer Research Dresden , Hohe Str. 6 , 01069 Dresden , Germany
| | - Marina Saphiannikova
- Institute Theory of Polymers , Leibniz Institute of Polymer Research Dresden , Hohe Str. 6 , 01069 Dresden , Germany
- Dresden Center for Computational Materials Science (DCMS) , Technische Universität Dresden , 01062 Dresden , Germany
| | - Olga Guskova
- Institute Theory of Polymers , Leibniz Institute of Polymer Research Dresden , Hohe Str. 6 , 01069 Dresden , Germany
- Dresden Center for Computational Materials Science (DCMS) , Technische Universität Dresden , 01062 Dresden , Germany
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Henderson WR, Fagnani DE, Grolms J, Abboud KA, Castellano RK. Transannular Hydrogen Bonding in Planar‐Chiral [2.2]Paracyclophane‐Bisamides. Helv Chim Acta 2019. [DOI: 10.1002/hlca.201900047] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Will R. Henderson
- Department of ChemistryUniversity of Florida, PO Box 117200 Gainesville FL 32611–7200 USA
| | - Danielle E. Fagnani
- Department of ChemistryUniversity of Florida, PO Box 117200 Gainesville FL 32611–7200 USA
| | - Jonathan Grolms
- Department of ChemistryUniversity of Florida, PO Box 117200 Gainesville FL 32611–7200 USA
| | - Khalil A. Abboud
- Department of ChemistryUniversity of Florida, PO Box 117200 Gainesville FL 32611–7200 USA
| | - Ronald K. Castellano
- Department of ChemistryUniversity of Florida, PO Box 117200 Gainesville FL 32611–7200 USA
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