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Triplet state modification in organic phosphorescence molecules for a desired color and quantum yield is typically pursued by chemical modification. A facile methodology is introduced to tune the triplet state dynamics of a phosphorescent molecule by changing the host‐matrix parameters. An organic phosphor, Br2PmDI (2–Bromo pyromellitic diimide), dispersed at dilute levels (1.5 wt.%) in a semicrystalline high‐κ relaxer ferroelectric host matrix emit room‐temperature phosphorescence accompanied by a delayed fluorescence component. The host relaxer ferroelectric polymer film can be engineered to form a photonic matrix with a regular micropore structure of refractive index contrast ≈0.6 that can increase the density of optical states and introduce photonic coupling. The phosphorescence quantum yield of Br2PmDI in this photonic matrix increases by ≈2.3 fold, and the lifetime reduces by a factor of three. The coupled quantum states are investigated by time‐resolved spectroscopy at different temperatures and pump intensities. [ABSTRACT FROM AUTHOR]

Efficient circularly polarized luminescence (CPL) from purely organic molecules holds great promise for applications in displays, sensing, and bioimaging. However, achieving high dissymmetry values (glum) from organic chromophores remains a significant challenge. Herein, we present a bioinspired approach using adenosine triphosphate (ATP)‐triggered supramolecular polymerization of a naphthalene diimide‐derived monomer (ANSG) to induce CPL with a remarkable glum value of 1.1×10−2. The ANSG molecules undergo a templated, chiral self‐assembly through a cooperative growth mechanism in the presence of ATP, resulting in scrolled nanotubes with aggregation‐induced enhanced emission (AIEE) and induced CPL. Furthermore, we demonstrate the concept of chiroptical amplification of induced CPL by efficiently amplifying asymmetry using a mixture of chiral ATP and achiral pyrophosphate. This innovative approach opens numerous opportunities in the emerging field of circularly polarized luminescence. [ABSTRACT FROM AUTHOR]

Chiral organic phosphors with circularly polarized room‐temperature phosphorescence (CPP) provide new prospects to the realm of circularly polarized luminescence (CPL) materials, owing to the long‐lived triplet states and persistent emission. Although several molecular designs show efficient room‐temperature phosphorescence (RTP), realization of ambient organic CPP remains a formidable challenge. Herein, we introduce a chiral bischromophoric phosphor design to realize ambient CPP emission by appending molecular phosphors to a chiral diaminocyclohexane core. Thus, solution‐processable polymer films of the trans‐1,2‐diaminocyclohexane (DAC) chiral cores with heavy‐atom substituted pyromellitic diimide phosphors, exhibits one of the most efficient exclusive CPP emissions with high phosphorescence quantum yield (≈18 % in air and ≈46 % under vacuum) and significant luminescence dissymmetry factor (|glum|≈4.0×10−3). [ABSTRACT FROM AUTHOR]

Solution phase room‐temperature phosphorescence (RTP) from organic phosphors is seldom realized. Herein we report one of the highest quantum yield solution state RTP (ca. 41.8 %) in water, from a structurally simple phthalimide phosphor, by employing an organic–inorganic supramolecular scaffolding strategy. We further use these supramolecular hybrid phosphors as a light‐harvesting scaffold to achieve delayed fluorescence from orthogonally anchored Sulforhodamine acceptor dyes via an efficient triplet to singlet Förster resonance energy transfer (TS‐FRET), which is rarely achieved in solution. Electrostatic cross‐linking of the inorganic scaffold at higher concentrations further facilitates the formation of self‐standing hydrogels with efficient RTP and energy‐transfer mediated long‐lived fluorescence. [ABSTRACT FROM AUTHOR]

Synthesis of supramolecular block co‐polymers (BCP) with small monomers and predictive sequence requires elegant molecular design and synthetic strategies. Herein we report the unparalleled synthesis of tri‐component supramolecular BCPs with tunable microstructure by a kinetically controlled sequential seeded supramolecular polymerization of fluorescent π‐conjugated monomers. Core‐substituted naphthalene diimide (cNDI) derivatives with different core substitutions and appended with β‐sheet forming peptide side chains provide perfect monomer design with spectral complementarity, pathway complexity and minimal structural mismatch to synthesize and characterize the multi‐component BCPs. The distinct fluorescent nature of various cNDI monomers aids the spectroscopic probing of the seeded growth process and the microscopic visualization of resultant supramolecular BCPs using Structured Illumination Microscopy (SIM). Kinetically controlled sequential seeded supramolecular polymerization presented here is reminiscent of the multi‐step synthesis of covalent BCPs via living chain polymerization. These findings provide a promising platform for constructing unique functional organic heterostructures for various optoelectronic and catalytic applications. [ABSTRACT FROM AUTHOR]

Arylene diimide derived ambient organic phosphors are seldom reported despite their potential structural characteristics to facilitate the triplet harvesting. In this context, highly efficient room temperature phosphorescence (RTP) from simple, heavy‐atom substituted pyromellitic diimide derivatives in amorphous matrix and crystalline state is reported here. Multiple intermolecular halogen bonding interactions among these phosphors, such as halogen‐carbonyl and halogen‐π resulted in the modulation of phosphorescence, cyan emission from monomeric state and orange‐red emission from its aggregated state, to yield twin RTP emission. Remarkably, the air‐stable phosphorescence presented here own one of the highest quantum yield (≈48 %) among various organics in orange‐red emissive region. [ABSTRACT FROM AUTHOR]

Fuel‐regulated self‐assembly is a key principle by which Nature creates spatiotemporally controlled materials and dynamic molecular systems that are in continuous communication (molecular exchange) with the external environment. Designing artificial materials that self‐assemble and disassemble via conversion/consumption of a chemical fuel is a grand challenge in supramolecular chemistry, which requires a profound knowledge of the factors governing these complex systems. Here we focus on recently reported metal‐coordinated monomers that polymerise in the presence of ATP and depolymerise upon ATP hydrolysis, exploring their fuel‐regulated self‐assembly/disassembly via multiscale molecular modelling. We use all‐atom simulations to assess the role of ATP in stabilising these monomers in assemblies, and we then build on a minimalistic model to investigate their fuel‐driven polymerisation and depolymerisation on a higher scale. In this way, we elucidate general aspects of fuel‐regulated self‐assembly that are important toward the rational design of new types of bioinspired materials. [ABSTRACT FROM AUTHOR]

Adenosine triphosphate (ATP) is a molecular unit of energy that drives various processes in the cellular environment. In this Minireview, we discuss the potential of physical and chemical properties of ATP for the development of bio‐inspired, synthetic ATP‐induced supramolecular systems with dynamic, stimuli‐responsive and active assembly characteristics. Molecular design rules for ATP‐induced assemblies with various architectures and their stimuli‐responsive structural and functional response are categorized. Special attention is given to the immense potential of ATP‐fuelled designs in the nascent field of transient/non‐equilibrium supramolecular polymerization for the synthesis of lifelike temporally programmable soft materials. Finally, the existing dearth and fate of ATP‐driven systems for future challenges are discussed. [ABSTRACT FROM AUTHOR]

Transient supramolecular self‐assembly has evolved as a tool to create temporally programmable smart materials. Yet, so far single‐component self‐assembly has been mostly explored. In contrast, multicomponent self‐assembly provides an opportunity to create unique nanostructures exhibiting complex functional outcomes, newer and different than individual components. Even two‐component can result in multiple organizations, such as self‐sorted domains or co‐assembled heterostructures, can occur, thus making it highly complex to predict and reversibly modulate these microstructures. In this study, we attempted to create active bicomponent nanoparticle assemblies of orthogonally pH‐responsive‐group‐functionalized gold and cadmium selenide nanoparticles with temporal microstructural control on their composition (self‐sorted or co‐assembly) in order to harvest their emergent transient photocatalytic activity by coupling to temporal changes in pH. Moving towards multicomponent systems can deliver next level control in terms of structural and functional outcomes of supramolecular systems. [ABSTRACT FROM AUTHOR]

Stereoselective and temporally controlled supramolecular polymerizations are ubiquitous in nature and are desirable attributes for the design of chiral, well‐defined functional materials. Kinetically controlled, living supramolecular polymerization (LSP) has emerged recently for the synthesis of supramolecular polymers with controlled length and narrow dispersity. On the other hand, stringent design requirements for chiral‐discriminating monomers precludes the stereoselective control of the supramolecular polymer structure. Herein, a synergetic stereo‐ and structural control of supramolecular polymerization by the realization of an unprecedented stereoselective seed‐induced LSP is reported. Homochiral and seeded growth is demonstrated with bischromophoric naphthalene diimide (NDI) enantiomers with a chiral binaphthyl amine core, exhibiting strong self‐recognition abilities and pathway complexity. [ABSTRACT FROM AUTHOR]

Organic molecules exhibiting afterglow emission (lifetime longer than 0.1 s) under ambient conditions have sparked tremendous attention in recent years as a sustainable energy source with potential applications in displays, lighting, and bioimaging. However, white afterglow organic materials with color purity during the entire period of delayed emission, after the cessation of excitation source, are yet to be achieved due to the different excited state lifetimes of its primary or complementary components. Herein, a remarkable, ambient "temporally pure white afterglow," which lasts for over 7 s, by coorganizing complementary blue and greenish‐yellow organic room temperature phosphors with similar ultralong lifetimes and efficiency, in an amorphous polymer film is demonstrated. One of the most efficient blue afterglow room temperature phosphors is also reported, with an ultralong lifetime up to 2.26 s and maximum quantum efficiency of 36.8%, from purely organic triazatruxenes en route to the realization of this white afterglow. Further, broad and complementary absorption features of the coorganized phosphors in the visible region facilitates an excitation‐dependent dynamic color‐tuning of the afterglow from sky‐blue to greenish‐yellow. [ABSTRACT FROM AUTHOR]

Herein, we present the self‐assembly and chiroptical properties of enantiomeric bischromophoric molecules consisting of trans‐(1,2)‐cyclohexanediamide as the chiral core and cyanostilbene derivative as the fluorescent chromophores. These enantiomers form diverse organic nanostructures, such as vesicles and two‐dimensional sheets, in non‐polar solvents, exhibiting circularly polarized luminescence (CPL) with a remarkable luminescence dissymmetry factor, |glum|, in solution. Detailed spectroscopic probing reveals the formation of supramolecular conglomerate assemblies from its racemic mixture of monomers due to the chirality mismatch of the core. [ABSTRACT FROM AUTHOR]

Ambient afterglow luminescence from metal‐free organic chromophores would provide a promising alternative to the well‐explored inorganic phosphors. However, the realization of air‐stable and solution‐processable organic afterglow systems with long‐lived triplet or singlet states remains a formidable challenge. In the present study, a delayed sensitization of the singlet state of organic dyes via phosphorescence energy transfer from organic phosphors is proposed as an alternative strategy to realize "afterglow fluorescence". This concept is demonstrated with a long‐lived phosphor as the energy donor and commercially available fluorescent dyes as the energy acceptor. Triplet‐to‐singlet Förster‐resonance energy‐transfer (TS‐FRET) between donor and acceptor chromophores, which are co‐organized in an amorphous polymer matrix, results in tuneable yellow and red afterglow from the fluorescent acceptors. Moreover, these afterglow fluorescent hybrids are highly solution‐processable and show excellent air‐stability with good quantum yields. [ABSTRACT FROM AUTHOR]

Dissipative systems, that constantly consume energy for sustenance, are ubiquitous and essential to life. In synthetic systems, the phenomenon promises emergent properties and different structure from the ones existing at thermodynamic equilibrium. It can create reconfigurable and temporally programmable life‐like smart materials. In this study, we attempt to create reconfigurable, temporally programmable self‐assembly using the redox chemistry of a core‐substituted naphthalene diimide derivative. As a result, transient reconfiguration of supramolecular assembly from vesicle to sheet along with transient fluorescence switching with fuel‐dependent lifetime is attained. We believe that such a design strategy can advance the synthesis of active, adaptive and autonomous materials. [ABSTRACT FROM AUTHOR]

The pH‐responsive nature of two self‐assembled NDI‐peptide amphiphile conjugates is reported. The diethoxy substituted NDI showed a pH‐dependent assembly behaviour, as expected. In contrast, the isopropylamino‐ and ethoxy‐substituted NDI based supramolecular polymer was stable at acidic and basic aqueous conditions. This finding highlights how subtle changes in the molecular design of π‐stacked chromophore‐peptide conjugates have a drastic impact on their equilibrium structure and ultimately functional properties. [ABSTRACT FROM AUTHOR]

Unprecedented ambient triplet‐mediated emission in core‐substituted naphthalene diimide (cNDI) derivatives is unveiled via delayed fluorescence and room temperature phosphorescence. Carbazole core‐substituted cNDIs, with a donor–acceptor design, showed deep‐red triplet emission in solution processable films with high quantum yield. This study, with detailed theoretical calculations and time‐resolved emission experiments, enables new design insights into the triplet harvesting of cNDIs; an important family of molecules which has been, otherwise, extensively been investigated for its n‐type electronic character and tunable singlet fluorescence. [ABSTRACT FROM AUTHOR]

Viologen based covalent organic polymer (COP) interfaced with graphene at the nanoscale showed pseudocapacitive energy storage associated with redox‐active moieties. The positively charged viologen moieties endow charge storage as well as easy wetting of the electrode. The non‐conducting COP grown over conducting graphene enhances its performance by extensive interface formation. All the redox states of viologen moieties can be reversibly attained without significant polarization when it is interfaced with graphene. However, the COP (devoid of graphene) shows irreversible/pseudo‐reversible behavior due to lack of electron conducting pathways. The intimate and dense conducting pathways in graphene‐COP composites facilitates the charge transfer across interface leading to effective and reversible participation of redox moieties across the entire range over 1000 cycles. Also, we show that the strategy being universal in nature and aid in electron transfer in dense 3D networks which lacks traditional π‐π stacking of 2D crystalline networks (COF). [ABSTRACT FROM AUTHOR]

van der Waals heterostructures formed by 2D materials have attracted much attention in the last few years. Recently, 2D nanosheets linked by covalent bonds have been found to exhibit novel properties. In the present study we have investigated supramolecular layered heterostructures formed by nanosheets of MoS2 with BC7N, g‐C3N4 and graphene. These materials have been synthesized via a non‐covalent host–guest synthetic design using cucurbit[8]uril (CB[8]) hosts. In addition to offering reversible disassembly, these heterostructures show good visible‐light‐driven hydrogen evolution reaction (HER) activity as well as reasonable gas adsorption and other properties. [ABSTRACT FROM AUTHOR]

Ambient solution and amorphous state room temperature phosphorescence (RTP) from purely organic chromophores is rarely achieved. Remarkable stabilization of triplet excitons is realized to obtain deep red phosphorescence in water and in amorphous film state under ambient conditions by a unique supramolecular hybrid assembly between inorganic laponite clay and heavy atom core substituted naphthalene diimide (NDI) phosphor. Structural rigidity and oxygen tolerance of the inorganic template along with controlled molecular organization via supramolecular scaffolding are envisaged to alleviate the unprecedented aqueous phase phosphorescence. Aqueous phosphorescence: An unprecedented organic‐inorganic hybrid co‐assembly approach is proposed to obtain aqueous state as well as amorphous red‐emitting room temperature phosphorescence. Heavy‐atom effect in the NDI derivative along with its J‐aggregation enhance the intersystem crossing efficiency whereas rigid and oxygen tolerant laponite templates stabilize the triplets. [ABSTRACT FROM AUTHOR]

Chirality-driven self-sorting is envisaged to efficiently control functional properties in supramolecular materials. However, the challenge arises because of a lack of analytical methods to directly monitor the enantioselectivity of the resulting supramolecular assemblies. Presented herein are two fluorescent core-substituted naphthalene-diimide-based donor and acceptor molecules with minimal structural mismatch and they comprise strong self-recognizing chiral motifs to determine the self-sorting process. As a consequence, stereoselective supramolecular polymerization with an unprecedented chirality control over energy transfer has been achieved. This chirality-controlled energy transfer has been further exploited as an efficient probe to visualize microscopically the chirality driven self-sorting. [ABSTRACT FROM AUTHOR]

Synthetic manifestations of supramolecular chirality have extensively drawn inspiration from naturally occurring systems. Even though in biological systems conformational changes are dissipative, synthetic systems that change conformation under non-equilibrium conditions have still not been established. Herein, we attempt to alleviate this scenario by reporting a synthetic supramolecular system that undergoes temporal changes in its helical conformation as an active system at the expense of a biologically relevant chemical fuel, ATP. Use of enzymes working in tandem provides transient and switchable helices with modular lifetime and stereomutation rates. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we explore the use of supramolecular nanofibers as an electrolyte for in‐plane micro‐supercapacitors. The supramolecular nanofibers obtained from the self‐assembly of donor–acceptor (D‐A) molecules, coronene tetracarboxylate salt (CS) and dodecyl methyl viologen (DMV), carrying positive and negative ionic charges, respectively, were drop‐coated onto metal gap electrodes using an aqueous dispersion to form the device. Under dry conditions (<35 % relative humidity, RH), the device exhibited a stack capacitance of 160 F cm−3 with energy and power densities comparable to high‐performance micro‐supercapacitors. Although the electrolyte has aqueous origin, in dry conditions, it is capable of operating in a voltage window of 0–3 V. This supramolecular micro‐supercapacitor device (micro‐SS) was fabricated only with metal electrodes without using electrode material in it, thanks to the ability of the nanofiber to provide extended surface area for charge storage. The 1D face‐to‐face arrangement of D‐A molecules seems to provide an efficient pathway for the diffusion of ions across the electrodes. The present study not only provides a new approach to obtain an ambient stable electrolyte with wide operating voltage window but also gives a low‐cost method of fabricating micro‐supercapacitors with reasonably high energy and power densities. [ABSTRACT FROM AUTHOR]

A 'chirality driven self-sorting' strategy is introduced for the controlled supramolecular organization of donor (D) and acceptor (A) molecules in multicomponent assemblies. The trans-1,2-bis(amido)cyclohexane ( trans-BAC) has been identified as a supramolecular motif with strong homochiral recognition to direct this chirality controlled assembly process of enantiomers in solution. Stereoselective supramolecular polymerization of trans-BAC appended naphthalene diimide monomers (NDIs) has been probed in detail by spectroscopic and mechanistic investigations. This chirality-driven self-sorting design of enantiomeric components also offers to realize mixed and segregated D-A stacks by supramolecular co-assembly of the NDI acceptors with trans-BAC appended dialkoxynaphthalene (DAN) donor monomers. Such an unprecedented chirality control on D-A organization paves the way for the creation of supramolecular p-n nanostructures with controlled molecular-level organization. [ABSTRACT FROM AUTHOR]

Molecular organization of donor and acceptor chromophores in self-assembled materials is of paramount interest in the field of photovoltaics or mimicry of natural light-harvesting systems. With this in mind, a redox-active porous interpenetrated metal-organic framework (MOF), {[Cd(bpdc)(bpNDI)] ⋅4.5 H2O ⋅DMF} n ( 1) has been constructed from a mixed chromophoric system. The μ-oxo-bridged secondary building unit, {Cd2(μ-OCO)2}, guides the parallel alignment of bpNDI ( N,N′-di(4-pyridyl)-1,4,5,8-naphthalenediimide) acceptor linkers, which are tethered with bpdc (bpdcH2=4,4′-biphenyldicarboxylic acid) linkers of another entangled net in the framework, resulting in photochromic behaviour through inter-net electron transfer. Encapsulation of electron-donating aromatic molecules in the electron-deficient channels of 1 leads to a perfect donor-acceptor co-facial organization, resulting in long-lived charge-separated states of bpNDI. Furthermore, 1 and guest encapsulated species are characterised through electrochemical studies for understanding of their redox properties. [ABSTRACT FROM AUTHOR]

Several covalent strategies towards surface charge-reversal in nanochannels have been reported with the purpose of manipulating ion transport. However, covalent routes lack dynamism, modularity and post-synthetic flexibility, and hence restrict their applicability in different environments. Here, we introduce a facile non-covalent approach towards charge-reversal in nanochannels (<10 nm) using strong charge-transfer interactions between dicationic viologen (acceptor) and trianionic pyranine (donor). The polarity of ion transport was switched from anion selective to ambipolar to cation selective by controlling the extent of viologen bound to the pyranine. We could also regulate the ion transport with respect to pH by selecting a donor with pH-responsive functional groups. The modularity of this approach further allows facile integration of various functional groups capable of responding to stimuli such as light and temperature to modulate the transport of ions as well as molecules. [ABSTRACT FROM AUTHOR]

Flexible and dynamic porous coordination polymers (PCPs) with well-defined nanospaces composed of chromophoric organic linkers provide a scaffold for encapsulation of versatile guest molecules through noncovalent interactions. PCPs thus provide a potential platform for molecular recognition. Herein, we report a flexible 3D supramolecular framework {[Zn(ndc)( o-phen)]⋅DMF} n ( o-phen=1,10-phenanthroline, ndc=2,6-napthalenedicarboxylate) with confined nanospaces that can accommodate different electron-donating aromatic amine guests with selective turn-on emission signaling. This system serves as a molecular recognition platform through an emission-readout process. Such unprecedented tunable emission with different amines is attributed to its emissive charge-transfer (CT) complexation with o-phen linkers. In certain cases this CT emission is further amplified by energy transfer from the chromophoric linker unit ndc, as evidenced by single-crystal X-ray structural characterization. [ABSTRACT FROM AUTHOR]

Charge-transfer (CT) assemblies of aromatic donor (D) and acceptor (A) molecules have recently gained attention as a promising material for organic electronics and ferroelectrics. Two major factors which govern their functions are the strength of CT interaction and their supramolecular nanostructuring. Here we present coronene-naphthalenediimide (NDI)-based novel D-A pairs that form alternately stacked CT assemblies. Through systematic substitution of the NDI derivatives and studying their CT interactions with coronene, a clear understanding of the secondary forces responsible for controlling their association is gained. Finally, the use of CT-based supramolecular amphiphiles for their nanostructural engineering into ordered one-dimensional (1-D) assemblies is demonstrated. [ABSTRACT FROM AUTHOR]

Metal-organic vesicular and toroid nanostructures of Zn(OPE)·2H2O are achieved by coordination-directed self-assembly of oligo-phenyleneethynylenedicarboxylic acid (OPEA) as a linker with Zn(OAc)2 by controlling the reaction parameters. Self-assembled nanostructures are characterized by powder X-ray diffraction, field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), and adsorption study. The amphiphilic nature of the coordination-polymer with long alkyl chains renders different soft vesicular and toroidal nanostructures. The permanent porosity of the framework is established by gas adsorption study. Highly luminescent 3D porous framework is exploited for Froster's resonance energy transfer (FRET) by encapsulation of a suitable cationic dye ( DSMP) which shows efficient funneling of excitation energy. These results demonstrate the dynamic and soft nature of the MOF, resulting in unprecedented vesicular and toroidal nanostructures with efficient light harvesting applications. [ABSTRACT FROM AUTHOR]

We describe the preparation and optical characterisation of a coronene tetracarboxylate salt (CS) in polyvinyl alcohol (PVA) thin film solutions processed from water, neat or mixed with varying ratios of a europium tris(hexafluoroacetylacetoanto) diaquo complex [Eu(hfac)3(H2O)2]. Neat CS-PVA showed not only well-defined fluorescence peaks but also a long-lived phosphorescence emission, persisting for more than 1 second. Interaction between the CS and EuIII molecules, mediated by means of carboxylate coordination to the EuIII, was attained by simple incorporation into the PVA polymer matrix and resulted in energy transfer from the coronone antenna to the europium centre. Under various blend ratios of CS and the EuIII complex, total photoluminescence quantum yields of typically around 30% were achieved. The straightforward processing of this type of self-assembled chromophore-lanthanide system into a luminescent polymer film offers potential for application to other chromophores, lanthanides and polymers. [ABSTRACT FROM AUTHOR]

A novel supramolecular clipping design for influencing the photophysical properties of functional molecular assemblies, by the preorganization (clipping) of chromophores, is described. Several chromophores end functionalized with molecular recognition units were designed. These molecular recognition units serve as handles to appropriately position these systems upon noncovalent interactions with multivalent guest molecules (supramolecular clippers). Towards this goal, we have synthesized 1,5-dialkoxynaphthalene (DAN) and naphthalenediimide (NDI) functionalized with dipicolylethylenediamine (DPA) motifs. These molecules could preorganize upon noncovalent clipping with adenosine di- or triphosphates, which resulted in preassociated excimers and mixed (cofacial) charge-transfer (CT) assemblies. Chiral guest binding could also induce supramolecular chirality, not only into the individual chromophoric assembly but also into the heteromeric CT organization, as seen from the strong circular dichroism (CD) signal of the CT transition. The unique ability of this design to influence the intermolecular interactions by changing the binding strength of the clippers furthermore makes it very attractive for controlling the bimolecular photophysical processes. [ABSTRACT FROM AUTHOR]

Self-assembly of carbonate linkage bearing naphthalene diimides (NDI) showed unusually red-shifted excimer emission at approximately 560 nm. On the other hand, the ether linkers showed usual excimers at around 520 nm, highlighting the role of the carbonate group in tuning the molecular organization and the resultant photophysical properties of NDI. [ABSTRACT FROM AUTHOR]

Oligo( p-phenylenevinylenes) (OPVs) with amphiphilic character are synthesized and their self-assembly characteristics studied. Careful studies point at two morphologically different states of assemblies, with one being two dimensional sheets and the other as rolled tubes. This is also the first time that self-assembled sheets are achieved for OPVs. Morphological and photo-physical studies reveal a unique aggregate to aggregate transition between rolled tubes and two dimensional sheets, which is outlined as a more thermodynamic aggregate. The thermodynamic aggregate (2D sheet) is better ordered and consists of chromophores that are better excitonically coupled. The mobilities of these aggregates are also studied for a field effect transistor device and as expected sheets supersede rolled tubes by a couple of orders. More interestingly, the mobility values obtained for the well ordered chromophores in sheets is three orders higher than any other self-assembled OPV previously reported. It is hypothesized that the better π interactions enforced by the amphiphilic design and the resultant supramolecular organization is a prime factor for such a remarkable rise in mobilities. [ABSTRACT FROM AUTHOR]

The study of the organization of small π-conjugated molecules is imperative to understanding and controlling its properties for various applications. Coronene bisimides (CBIs) are potential candidates for novel liquid-crystalline materials and active n-type semiconductor molecules in organic electronics. To understand the self-assembly of this seldom-studied chromophore, we have designed two derivatives of CBIs bearing chiral and achiral 3,4,5-trialkoxyphenyl groups at the imide position, named as CBI-GCH and CBI-GACH, respectively. CBI-GCH self-assembles mainly through π-stacking and van der Waals interactions in nonpolar methylcyclohexane to result in long 1D fibrillar stacks. The mechanism of supramolecular polymerization was probed by using chiroptical studies, which showed an isodesmic pathway for CBI-GCH. The thermodynamic parameters that govern the self-assembly are detailed. CBI-GACH also shows similar self-assembly behavior as its chiral counterpart. X-ray diffraction studies of both molecules reveals a 2D hexagonal columnar arrangement. The coassembly of CBI-GCH and CBI-GACH shows chiral amplification (sergeant and soldiers experiment) with saturation at 30-50 % of the chiral derivative, which was further used to study the dynamics of the assembly. Thus, this study presents a rare report of chiral amplification in an isodesmic system. [ABSTRACT FROM AUTHOR]