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Abstract Organic thin films are at the forefront of basic studies and applications in the field of physics, chemistry, biochemistry and materials science. For example, the intrinsic supramolecular arrangement, or simply the formation of aggregates may alter the optical and electrical properties, which would impact the potential applications of the material. Here, an attempt is made to correlate the molecular structures of two perylene derivatives, bis butylimido perylene (BuPTCD) and bis phenethylimido perylene (PhPTCD), with their film formation, in particular, the supramolecular arrangement and the photoluminescent properties. Emission spectra show that the PhPTCD has a radiative efficiency (RE) higher than that for BuPTCD when both are in solutions (monomers). Complementary, regarding PVD films, UV–Vis absorption measurements reveal that PhPTCD forms, predominantly, J aggregates, which are responsible for perylene derivative emission. However, BuPTCD PVD films are found to provide higher RE than PhPTCD PVD film. This apparent controversy could be explained considering other features such as crystallinity and molecular organization. The PVD film of BuPTCD is crystalline while PhPTCD PVD film is amorphous; BuPTCD has an edge-on while PhPTCD has a face-on molecular organization in PVD films. Graphical Abstract Unlabelled Image Highlights • PhPTCD has a radiative efficiency higher than that for BuPTCD in solution. • PhPTCD forms, predominantly, J aggregates, which are responsible for its emission. • BuPTCD is found to provide higher radiative efficiency than PhPTCD in PVD film. • BuPTCD has oriented crystalline phase in PVD films, while for PhPTCD it is amorphous. • Both perylene derivative films have a different molecular organization in PVD films. [ABSTRACT FROM AUTHOR]

Abstract: Studies were carried out on the hierarchical self‐assembly versus pathway complexity of N‐annulated perylenes 1–3, which differ only in the nature of the linking groups connecting the perylene core and the side alkoxy chains. Despite the structural similarity, compounds 1 and 2 exhibit noticeable differences in their self‐assembly. Whereas 1 forms an off‐pathway aggregate I that converts over time (or by addition of seeds) into the thermodynamic, on‐pathway product, 2 undergoes a hierarchical process in which the kinetically trapped monomer species does not lead to a kinetically controlled supramolecular growth. Finally, compound 3, which lacks the amide groups, is unable to self‐assemble under identical experimental conditions and highlights the key relevance of the amide groups and their position to govern the self‐assembly pathways. [ABSTRACT FROM AUTHOR]

A supramolecular complex that can be selectively reduced to radical anions in situ by facultative anaerobic bacteria is reported. To this end, a water-soluble bifunctional monomer bearing perylene diimide was synthesized, and its supramolecular complex with cucurbit[7]uril was fabricated on the basis of host-guest complexation, which could be reduced to forming radical anions in the presence of E. coli. It was found that this supramolecular complex could display different ability of generating radical anions by facultative anaerobic and aerobic bacteria in terms of their various reductive abilities. The selective antibacterial activity of the supramolecular complex could be realized by the photothermal performance of the radical anions under near-infrared irradiation. It is anticipated that this method may lead to a novel bacteria-responsive photothermal therapy to regulate balance of bacterial flora. [ABSTRACT FROM AUTHOR]

Novel monoisomeric perylene imide derivatives with terpyridinyl and pyrrolidinyl substituents were synthesized and deposited onto solid substrates, such as a thin film of Al2O3 and mesoporous TiO2 nanoparticle layer, by using a simple dip-bydip method. Arrays of up to 33 layers were built on Al2O3. In the case of mesoporous TiO2, the interstitial volume between the particles was filled up with dye assemblies. Deposition could produce either layers of microcrystals or molecular layers if an appropriate washing procedure was used. The resultant arrays were studied by means of scanning electron microscopy, X-ray photoelectron spectroscopy measurements, and UV/Vis absorption. [ABSTRACT FROM AUTHOR]

The control over supramolecular interactions and obtaining information beyond the molecular scale is an extended challenge. The intriguing self-assembly of a perylene-3,4,9,10-tetracarboxylic acid diimide (PDI)-based novel bolaamphiphilic probe is experienced within an artificial environment that is restrained by using supramolecular crystallization and molecular recognition. The bolaamphiphile with a hydrophilic [18]-azacrown ether ring produced nanoaggregates due to differing solubilities in organic and aqueous media. A structural evolution was observed in the presence of alkali metal ions as guests. The metal complexes form a pseudo-cationic structure, which is further involved in an ionic self-assembly with biomolecules, thus resulting new spectroscopic information on the dye self-assembly. The overarching aim of this study is to emphasize the importance of the concept of supramolecular adaptability, which has been used to establish an environment-friendly behavior based on noncovalent forces, thus leading to the evolution of new assembly structures and photophysical properties. [ABSTRACT FROM AUTHOR]

Supramolecular self-assembly has attracted increasing attention as a breakthrough methodology in the fields of nanoscience and nanotechnology. Herein, a perylene dianhydride derivative (TP-PDA) self-assembles into well-defined nanospheres through a nucleation-growth process. The mechanisms of this process were explored by using spectral analysis, dynamic light scattering (DLS), and scanning electron microscopy (SEM). In situ DLS and in situ SEM both revealed that the size of the aggregated nanospheres increases with time until the formation of equilibrium H-aggregates. This shows that TP-PDA undergoes a kinetically trapped assembly with a rapid transformation into the thermodynamically favored form, and this process can be finely tuned by reducing the concentration and increasing the temperature. Weak intermolecular forces, such as π-π stacking, hydrogen bonding, and solvophobic interactions, play an important role in the formation of nanostructures. This work inspired us to explore other kinetically trapped supramolecular assemblies that might be easily ignored due to the short trapping time of commonly used experimental timescales. [ABSTRACT FROM AUTHOR]

The article focuses on the study conducted by the authors on formation of graphene-based hierarchical architectures by non-covalent chemical functionalization of pristine graphite with perylene diimide (PDI) surfactants. It is suggested that by the exfoliation of graphite and the attachment of tailor-made cationic PDI surfactants to FLG fl akes, positively charged functionalized 2D graphene-based hybrids can be formed and formation of ultrathin films is described.

Halogen bonding has emerged as a popular synthon in supramolecular architectures. Its effects on supramolecular perylene systems however have been under investigated. We report X…O halogen bonding of perylene-3,4,9,10-tetracarboxylic tetra esters. This templates a twisted perylene core which affects its spectral properties. We show this interaction exists in both the solution and solid state through spectroscopy studies and single crystal analysis. [ABSTRACT FROM AUTHOR]

Sequential insertion of different dyes into the 1D channels of zeolite L (ZL) leads to supramolecular sandwich structures and allows the formation of sophisticated antenna composites for light harvesting, transport, and trapping. The synthesis and properties of dye molecules, host materials, composites, and composites embedded in polymer matrices, including two- and three-color antenna systems, are described. Perylene diimide (PDI) dyes are an important class of chromophores and are of great interest for the synthesis of artificial antenna systems. They are especially well suited to advancing our understanding of the structure-transport relationship in ZL because their core fits tightly through the 12-ring channel opening. The substituents at both ends of the PDIs can be varied to a large extent without influencing their electronic absorption and fluorescence spectra. The intercalation/insertion of 17 PDIs, 2 terrylenes, and 1 quaterrylene into ZL are compared and their interactions with the inner surface of the ZL nanochannels discussed. ZL crystals of about 500 nm in size have been used because they meet the criteria that must be respected for the preparation of antenna composites for light harvesting, transport, and trapping. The photostability of dyes is considerably improved by inserting them into the ZL channels because the guests are protected by being confined. Plugging the channel entrances, so that the guests cannot escape into the environment is a prerequisite for achieving long-term stability of composites embedded in an organic matrix. Successful methods to achieve this goal are described. Finally, the embedding of dye-ZL composites in polymer matrices, while maintaining optical transparency, is reported. These results facilitate the rational design of advanced dye-zeolite composite materials and provide powerful tools for further developing and understanding artificial antenna systems, which are among the most fascinating subjects of current photochemistry and photophysics. [ABSTRACT FROM AUTHOR]

The facile assembly of shell-by-shell (SbS)-coated nanoparticles [TiO2PAC16]@shell 1- 7 (PAC16=hexadecylphosphonic acid), which are soluble in water and can be isolated as stable solids, is reported. In these functional architectures, an umpolung of dispersibility (organic apolar versus water) was accomplished by the noncovalent binding of ligands 1- 7 to titania nanoparticles [TiO2PAC16] containing a first covalent coating with PAC16. Ligands 1- 7 are amphiphilic and form the outer second shell of [TiO2PAC16]@shell 1- 7. The tailor-designed dendritic building blocks 3- 5 contain negative and positive charges in the same molecule, and ligands 6 and 7 contain a perylenetetracarboxylic acid dimide (PDI) core ( 6/ 7) as a photoactive reporter component. In the redox and photoactive system [TiO2PAC16]@shell 7, electronic communication between the inorganic core to the PDI ligands was observed. [ABSTRACT FROM AUTHOR]

The mechanism of supramolecular polymerization has been elucidated for an archetype organogelator molecule composed of a perylene bisimide aromatic scaffold and two amide substituents. This molecule selfassembles into elongated one-dimensional nanofibers through a cooperative nucleation-growth process. Thermodynamic and kinetic analyses have been applied to discover conditions (temperature, solvent, concentration) where the spontaneous nucleation can be retarded by trapping of the monomers in an inactive conformation, leading to lag times up to more than 1 h. The unique kinetics in the nucleation process was confirmed as a thermal hysteresis in a cycle of assembly and disassembly processes. Under appropriate conditions within the hysteresis loop, addition of preassembled nanofiber seeds leads to seeded polymerization from the termini of the seeds in a living supramolecular polymerization process. These results demonstrate that seeded polymerizations are not limited to special situations where off-pathway aggregates sequester the monomeric reactant species but may be applicable to a large number of known and to be developed molecules from the large family of molecules that self-assemble into one-dimensional nanofibrous structures. Generalizing from the mechanistic insight into our seeded polymerization, we assert that a cooperative nucleation--growth supramolecular polymerization accompanied by thermal hysteresis can be controlled in a living manner. [ABSTRACT FROM AUTHOR]

Highlights: [•] The perylene derivative was acted as signal enhancer for system. [•] The perylene derivative was loaded on gold nanoparticles functionalized graphene via π–π stacking. [•] A sandwich-type ECL immunosensor was developed for AFP detection. [ABSTRACT FROM AUTHOR]

We report here a potassium-induced guanine quadruplex as a supramolecular platform for controlled assembly of electron donor–acceptor systems. A monodisperse, C4-symmetric octamer of a guanine-perylene-3,4,9,10-bis(dicarboximide) conjugate (GPDI) was prepared in tetrahydrofuran. The two layers of cyclic guanine tetramers have the same direction of rotation, and the PDI moiety between the layers adopts a nearly eclipsed relationship (H-aggregation), as revealed by small- and wide-angle X-ray scattering, NMR spectroscopy, and steady-state UV/vis absorption. Following photoexcitation of the PDI moiety in the quadruplex, charge separation occurs in τCS = 98 ± 12 ps to give G+•-PDI-• that recombines in τCR = 1.2 ± 0.2 ns, which is >100 times longer than that in the monomeric GPDI dyad. The transient absorption spectrum of G+•-PDI-• within the GPDI quadruplex suggests the formation of a radical anion delocalized over the neighboring PDI units, and this result is consistent with the more favorable electrochemical reduction potential for PDIs in the quadruplex relative to the monomer. [ABSTRACT FROM AUTHOR]

Si-HMS were synthesized and characterized by XRD and N adsorption isotherm. Perylene derivative has been incorporated into its channels by impregnation method. And the resulting composite was characterized by absorption, fluorescence emission and fluorescence lifetime methods. The results indicated that perylene molecules in HMS presented spectra with broad bands, loss of vibrational structure, red shift of maxima and elongated lifetime. [ABSTRACT FROM AUTHOR]

Review: 57 refs. [ABSTRACT FROM AUTHOR]

Review: ca. 150 refs. [ABSTRACT FROM AUTHOR]