Computational Studies of Nanographene Systems: Extended Discotics, Covalently Linked “Supermolecules,” and Functionalized Supramolecular Assemblies

Ziogos, Orestis George; Konstantinopoulos, Stefanos; Tsetseris, Leonidas; Theodorou, Doros N.

doi:10.1021/acs.jpcc.8b04576

Cited by 7 publications

(5 citation statements)

References 99 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This type of FF has been successfully used in the literature for simulating a variety of functionalized PAH molecular crystals. [51][52][53] The accuracy of united-atom FF representations for aliphatic nanophases for molecular crystals made up by soluble molecules with core-shell morphologies has been thoroughly demonstrated in the literature, starting from the early studies of Maliniak 54 and Bast and Hentschke 55 and leading up to recent implementations for either structural and dynamical properties 51,56,57 and charge transfer properties. [58][59][60][61] Its suitability for MD simulations of tetracene derivatives is confirmed via validation of structural properties with respect to the available experimental information.…”

Section: Methodsmentioning

confidence: 99%

Identifying high-mobility tetracene derivatives using a non-adiabatic molecular dynamics approach

et al. 2020

Self Cite

View full text Add to dashboard Cite

The search for conductive soft matter materials with significant charge mobility under ambient conditions has been a major priority in organic electronics (OE) research. Alkylated tetracenes are promising cost-effective candidate molecules that can be synthesized using wet chemistry methods, resulting in columnar single crystals with pronounced structural stability at and above room temperature. A remarkable characteristic of these materials is the capability of tuning the tetracene core intracolumnar stacking pattern and the crystal melting point via the side chain length and type modifications. In this study, we examine the performance of a series of alkylated tetracenes as hole conducting materials using a novel atomistic simulation technique that allows us to predict both the charge transport mechanism and mobilities. Our simulations demonstrate that molecular wires of alkylated tetracenes are capable of polaronic hole conduction at room temperature, with mobility values ranging up to 21 cm 2 V À1 s À1 , thus rendering such materials a highly promising choice for flexible OE applications. As regards the charge transfer robustness, two promising tetracene derivatives are identified with the capability of seamless inter-wire polaron delocalization, alleviating possible transfer bottlenecks due to local molecular defects. Our findings suggest that alkylated tetracenes offer an attractive route towards flexible columnar OE materials with unprecedented hole mobilities. † Electronic supplementary information (ESI) available: Description of the FOBSH methodology; systems under study; utilized force field and molecular dynamics simulations details; reorganization energy and charge transfer integral calculations details; classical force field validation results; inverse participation ratio time series for the TMT molecular crystal. See

show abstract

Section: Methodsmentioning

confidence: 99%

Identifying high-mobility tetracene derivatives using a non-adiabatic molecular dynamics approach

et al. 2020

Self Cite

View full text Add to dashboard Cite

show abstract

“…The large π-conjugated core of HBC gives rise to strong, noncovalent interactions among adjacent molecules, as well as between molecules and the basal plane of graphite. Understanding the resulting self-assembly processes is essential for advances in HBC-based (nano)technologies. ,, Self-assembly of HBC derivatives has been studied in various environments, namely, in solution and in bulk, where 3D columnar supramolecular structures are formed, ,− and on surfaces, enabling programmed 2D nanopatterning. ,, Substituents at peripheral positions play a key role in controlling self-assembly behavior of HBC. For example, HBCs with appropriate alkyl substituents show thermal phase transitions between crystalline and liquid-crystalline phases, where the phase-transition temperature can be tuned by the length of the side chains. ,,, Self-assembly of HBCs can thus be controlled by heat, yet the use of other external stimuli as remote controls to regulate self-assembly of HBC-based materials has only been occasionally considered. , …”

Section: Introductionmentioning

confidence: 99%

Photomodulation of Two-Dimensional Self-Assembly of Azobenzene–Hexa-peri-hexabenzocoronene–Azobenzene Triads

et al. 2019

View full text Add to dashboard Cite

Achieving exquisite control over self-assembly of functional polycyclic aromatic hydrocarbons (PAH) and nanographene (NG) is essential for their exploitation as active elements in (nano)technological applications. In the framework of our effort to leverage their functional complexity, we designed and synthesized two hexa-peri-hexabenzocoronene (HBC) triads, p AHA and o AHA, decorated with two light-responsive azobenzene moieties at the pseudo-para and ortho positions, respectively. Their photoisomerization in solution is demonstrated by UV–vis absorption. 1H NMR measurements of o AHA suggested 23% of Z-form can be obtained at a photostationary state with UV irradiation (366 nm). Scanning tunneling microscopy imaging revealed that the self-assembly of p AHA and o AHA at the solid–liquid interface between highly oriented pyrolytic graphite (HOPG) and their solution in 1,2,4-trichlorobenzene can be modulated upon light irradiation. This is in contrast to our previous work using HBC bearing a single azobenzene moiety, which did not show such photomodulation of the self-assembled structure. Upon E-Z isomerization both p AHA and o AHA displayed an increased packing density on the surface of graphite. Moreover, p AHA revealed a change of self-assembled pattern from an oblique unit cell to a dimer row rectangular crystal lattice whereas the assembly of o AHA retained a dimer row structure before and after light irradiation, yet with a modification of the inter-row molecular orientation. Molecular mechanics/molecular dynamics simulations validated the self-assembly patterns of p AHA and o AHA, comprising azobenzenes in their Z-forms. These results pave the way toward use of suitably functionalized large PAHs, as well as NGs, to develop photoswitchable devices.

show abstract

“…54 In addition, the 2D contour plot featured stacking sequences reminiscent of the layered packing modes associated with graphite and graphite-like hydrocarbons such as AA, AA′, and AB (Figure S9, SI). 55,56 Graphitic AA-stacking arrangement represents atom-on-atom orientations covering the ideal cofacial (D 0 ) mode discussed previously. Associated with node-to-node molecular orbital overlap, the AA packing sequence favors charge transport.…”

Section: ■ Results and Discussionmentioning

confidence: 99%

In Silico Exploration for Maximal Charge Transport in Organized Tetrabenzoacenes through Pitch and Roll Displacements

2019

View full text Add to dashboard Cite

A series of π-conjugated tetrabenzoacenes (TBA), including nitrogen-(un)doped derivatives, are computationally evaluated to comprehend the correlation between intrinsic structural arrangements and charge-transport characteristics. The central chargetransport parameters such as reorganization energy and electronic coupling are individually tuned through peri substitutions, core substitutions, and/or π extension in TBA derivatives. On the basis of reorganization energies, nitrogen doping impeded the electron transport in TBA analogs owing to significant structural changes associated with the reduction process. Our approach employing mapping of dimeric arrangements of TBA, modulated via long (pitch) and short (roll) axes displacements of the molecular entities, versus charge transfer coupling disclosed potential charge-transport regions in addition to the ideal cofacial modes. Charge transport characteristics of molecular packing arrangements of TBA mimicking the different orientations of graphene bilayers were analyzed, providing insights into the possible material applicability of TBA derivatives. The transition from completely aligned graphitic AA packing sequence to slip-stacked AB and AA′ stacking domains revealed a dent in the charge-transport map owing to node−antinode interaction of the frontier molecular orbitals. TBA analogs encompassing the expanded π-system materialized highly displaced dimeric orientation from AB-type packing to occupy a hierarchy favoring higher charge transfer coupling than the AB type. Thus, realizing stable interchromophoric arrangements of small organic molecules through chemical or physical techniques to control their charge-transporting efficiencies is an indispensable step toward the generation of better organic electronic devices.

show abstract

Computational Studies of Nanographene Systems: Extended Discotics, Covalently Linked “Supermolecules,” and Functionalized Supramolecular Assemblies

Cited by 7 publications

References 99 publications

Identifying high-mobility tetracene derivatives using a non-adiabatic molecular dynamics approach

Identifying high-mobility tetracene derivatives using a non-adiabatic molecular dynamics approach

Photomodulation of Two-Dimensional Self-Assembly of Azobenzene–Hexa-peri-hexabenzocoronene–Azobenzene Triads

In Silico Exploration for Maximal Charge Transport in Organized Tetrabenzoacenes through Pitch and Roll Displacements

Contact Info

Product

Resources

About