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The supramolecular chemistry of chlorins which are the most abundant photosynthetic pigments is reviewed. In chlorophyll-protein complexes, ligation of the central magnesium atom can occur in two diastereomeric configurations. Light-harvesting complexes of purple bacteria are formed by the self-assembly of short polypeptides which bind bacteriochlorophylls into circular structures. The light-harvesting organelle of green photosynthetic bacteria, the so-called "chlorosome", is the most efficient natural antenna system and is formed by self-assembly of bacteriochlorophylls c, d or e without the help of a protein scaffold. Semisynthetic and fully synthetic mimics of these self-assembling bacteriochlorophylls have been prepared and their self-assemblies have been studied in detail in view of artificial light-harvesting systems. From a single crystal X-ray diffraction analysis, one could put into evidence hierarchic supramolecular interactions within such self-assembling systems. Interestingly, hydrogen bonding which all present models of bacteriochlorophyll self-assemblies contain as one of the important supramolecular interactions is absent in the fully synthetic mimics. [ABSTRACT FROM AUTHOR]

This chapter gives an overview of the ordering of dyes on atomically flat conductive surfaces as revealed by scanning tunneling microscopy. Scanning tunneling microscopy provides detailed insight into the arrangement of dyes on various surfaces and unravels novel properties which arise as a result of the interaction of the dyes with the substrate. These high-resolution studies have been motivated by the importance of interfacial layers in view of material and device properties. Typical examples are provided of popular dye systems, including conjugated oligomers and polymers. In addition, the supramolecular ordering of mixtures of dyes and two-dimensional chirality is discussed. Scanning tunneling microscopy goes beyond imaging and its ability to manipulate dye molecules, both mechanically and chemically, is discussed. Finally, the use of scanning tunneling microscopy as a spectroscopy tool for probing the electronic properties of dye layers on surfaces is highlighted. [ABSTRACT FROM AUTHOR]

Metallosupramolecular assemblies of dyes are of increasing interest as model systems for natural light harvesting and photosynthetic complexes as well as for potential applications in solar energy conversion, photonics and molecular electronics. Considerable efforts have been made in the past years to design novel metallosupramolecular dye architectures for such applications. Often in combination with other noncovalent interactions like hydrogen-bonding and π--π-stacking, metal-ion coordination has been utilized to achieve self-organization of dye building blocks into elaborate architectures with interesting optical and photophysical properties. Diverse metallosupramolecular dye assemblies -- macrocycles, polyhedra, polymers and dendrimers -- have been constructed in recent years by the metal-coordination approach. Here we review the recent advances in metallosupramolecular dye assemblies with particular attention to their thermodynamic stability and photophysical functionality. Emphasis is given to metal-ion mediated self-organization of porphyrin, metalloporphyrin and perylene bisimide dyes. [ABSTRACT FROM AUTHOR]

Several aspects of the intercalation of organic dyes into DNA are presented. After a description of general features of intercalation and the analytical evaluation of this binding mode, recent applications of the intercalation process in chemistry, biology, pharmacy, and medicine are described, with examples from representative dye classes, namely acridines, anthraquinones, cyanines, and phenanthridinium dyes. Along with references to classical work in this research field, examples are presented which demonstrate the influence of the substitution pattern of the intercalator on the selectivity and efficiency of intercalation. In addition, a survey of the recent literature is given that covers significant developments in the application of intercalating dyes as chemotherapeutic drugs, as probe or sensor molecules in biophysical chemistry and molecular biology, as photosensitizers in DNA-damage reactions, and as fluorescence stains. [ABSTRACT FROM AUTHOR]

In the last two decades the field of self-assembled monolayers (SAMs) has received much attention both in research and for applications because of the stability and the simple handling of SAMs. In this account we present a short overview about the morphology and preparation of the different gold surfaces used for SAMs and about self-assembled alkanethiol monolayers on Au(111). The synthetic strategies and the aggregation of self-assembled chromophores on gold is described in more detail. The most important chromophores are introduced along with their spectroscopic UV/vis, fluorescence, electron and energy transfer characteristics. Applications of self-assembled dyes on gold as sensors, photoswitchable materials, catalysts and for photocurrent generation are outlined. [ABSTRACT FROM AUTHOR]

Recent developments in the area of hydrogen-bonded supramolecular assemblies of functional dyes and extended π-conjugated systems are described. Emphasis is given to the hydrogen-bonded assemblies of dyes such as porphyrins, perylene bisimides, cyanines and azo compounds. In addition, a state-of-the-art summary of the recent developments in the design and properties of hydrogen-bonded supramolecular architectures of extended π-conjugated systems, that is oligomers and polymers, is presented. Finally, the current status of the design and studies of hydrogen-bonded π-conjugated gel systems and their application is described. [ABSTRACT FROM AUTHOR]

In this review, low molecular-weight organogel based on aromatic dye molecules and its stimuli-responsiveness were summarized. Aromatic dyes from small and medium aromatics such as azobenzene, pyrene, bithiophene, tropone, and merocyanine to large aromatics such as porphyrin, phthalocyanine, fullerene, triphenylene, hexaazatriphenylene, and phenylenevinylene, are self-assembled and self-organized in organogel systems to afford a new class of dye-based supramolecular assemblies. In certain solvents, aromatic dye molecules are stacked one-dimensionally to form the elongated columnar-type fibrous aggregates, which are entangled into three-dimensional network structures to prevent the solvents from flowing, leading to viscoelastic fluid "organogel". π--π stacking forces among core aromatic moieties and secondary noncovalent interactions such as hydrogen-bonding and van der Waals interactions cooperatively stabilize the supramolecular structures constructed in the organogel. The noncovalent assembling in the organogel organization is reflected in their reversible sol-gel phase transition controlled by physical or chemical stimuli such as thermo-, photo-, chemo-, metal-, proton-, and mechano-stimuli. By utilizing the columnar-type fibrous structure and the stimuli-responsiveness, the organogels can be engineered to show novel functions such as guest-recognizing, light-harvesting, carrier-transporting, and memory storage properties in soft materials. [ABSTRACT FROM AUTHOR]