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The addition of monovalent, divalent, and trivalent metal ions to three anionic ethyl meso-thiacarbocyanine dyes, an ethyl meso-oxacarbocyanine, and an imidacarbocyanine in aqueous solution at room temperature results in the production of J-aggregates within the range of tens to hundreds of seconds. The rate of formation of J-aggregates correlates with the rate of decay of dimers or monomers and is dependent on the type of metal ion, dye structure, and temperature. The rate of formation of J-aggregates increases as the temperature decreases and the dye and salt concentrations increase, and the rate is highest for trivalent ions and smallest for monovalent ions, independent of the type of anion. The time course of formation of J-aggregates is described in most cases by a sigmoidal curve, and the kinetics and mechanism are discussed within the framework of autocatalysis. Computer simulations reveal that the sigmoidal time dependence is transferred to an exponential-like curve by substantially increasing the rate constant for the noncatalytic step. The reaction pathway into J-aggregates can be switched from dimeric ion pairs as the reactant to monomeric ion pairs, when the rate constant for the catalytic step via the monomer becomes larger with respect to that via the dimer. [ABSTRACT FROM AUTHOR]

Two isomeric two-dimensional copper(I) coordination polymer materials based on an in situ generated 5-(3-pyridyl) te trazole ligand show similar layer structures but distinct photoluminescent and photo-catalytic properties, which present an interesting com-parative study on the structure--property correlation between isomeric materials. [ABSTRACT FROM AUTHOR]

Pb3O4 could react with organic dyes in aqueous solution under visible light irradiation, in which Pb3O4 was transformed into Pb3(CO3)2(OH)2 along with oxidation of the organic dyes. Cu2+ has considerable effect on the reaction. In the presence of Cu2+, MO (20 ppm) and RhB (10-5 mol L-1) were completely degraded under visible light within 6 and 20 min, respectively, while both Pb3O4 and Cu2+ keep almost stable during photo-degradation. The mechanisms of the reactions with and without Cu2+ ions were studied. The photochemical system of Pb3O4 cooperating with Cu2+ ions is probably used for the treatment of organic pollutants in water under visible light. [ABSTRACT FROM AUTHOR]

The article presents a study which examines the development of a new technology for spatially and temporally controlled drug delivery based on gold nanocontainers. It reveals that the technology is leakage-free, responsive to light irradiation, monodisperse, spectrally programmable, and provides important mechanism for drug release profiles. It mentions that these attributes were realized through the employment of cargo molecules, organic dye, and the anticancer drug known as doxorubicin.

The article presents a study which proposes the first molecular system that demonstrates the feasibility of altering the fluorescence properties of an organic dye as a function of radionuclide decay. The study found a clear differentiation in fluorescence between Cu2+ and its decay products. According to the researchers, the new molecular construct and mechanism could be used to develop visible radioactivity decay devices for environmental and nuclear forensic applications.

The article presents a study which describes the new homogeneous system for the photocatalytic production of H2 from aqueous protons using high absorbing organic dyes and a cobalt molecular catalyst. It states that a homogeneous photocatalytic hydrogen evolving system has been constructed form earth abundant and inexpensive components. The effect of pH on the initial rate of photocatalytic H2 production from a system composed of 1,5, and TEOA and MeCN/H2O 1:1.

The article demonstrates the optical properties of mixtures of quantum dots (QDs) and compares the results to fluorescent organic dyes. It is noted that the solutions of mixtures of QDs of different sizes produce colors that are the sum of the fluorescence wavelenghts of the individual QD components. To further understand why mixtures of quantum dots and organic dyes have different appearances, optical properties of both quantom dots and organic dyes are measured using absorption and fluorescence emission spectroscopy.

We report the visible-light-induced radical coupling reaction of silyl enol ethers with α-bromocarbonyl compounds to give 1,4-dicarbonyls. The reaction was effectively accelerated using an inexpensive organic dye (eosin Y) as a photoredox catalyst. 1,4-Dicarbonyl compounds alone were afforded, without the generation of carbonyl adducts of the α-halocarbonyls, which are usually generated in the presence of fluoride anions or Lewis acids. A variety of silyl enol ethers, α-bromoketones, α-bromoesters, and α-bromoamides were applied to this system to produce the coupling compounds. [ABSTRACT FROM AUTHOR]

The article describes the design and synthesis of a molar extinction organic sensitizer coded C203 with a fused dithienothiophene unit for efficient and stable dye-sensitized solar cells. According to the authors, a ~7% cell with an organic dye showing an excellent stability measured under the thermal and light-soaking dual stress was demonstrated in combination with a solvent-free ionic liquid electrolyte.

The article presents a study that investigates the problems being encountered in dye sensitized solar cells and in organic dyes. Researchers established that, based on the collected literature and a test ran for a number of phthalocyanine dyes, output voltages of most of the organic dyes are lower compared to equivalent cells generated with the use of N719.

The article offers information about a study that explores the use of alkyl-functionalized organic dyes for efficient molecular photovoltaics. This study is in line with the considerably increasing interest in organic devices such as light-emitting diodes, field effect transistors, and photovoltaic cells whose performance depend mainly on the properties of the functionalized organic molecules.

A correction to the article "Alkyl-Functionalized Organic Dyes for Efficient Molecular Photovoltaics," by Nagatoshi Komura, Zhong-Sheng Wang, Shogo Mori, Masanori Miyashita, Eiji Suzuki and Kohjiro Hara published in a 2006 issue is presented.