|
PTCDA
Perylenetetracarboxylic dianhydride (PTCDA) is an organic dye molecule and an organic semiconductor. It is used as a precursor to a class of molecules known as Rylene dyes, which are useful as pigments and dyes. It is a dark red solid with low solubility in aromatic solvents. The compound has attracted much interest as an organic semiconductor. Structure PTCDA consists of a perylene core to which two anhydride groups have been attached, one at either side. It occurs in two crystalline forms, α and β. Both have the P21/c monoclinic symmetry and a density of ca. 1.7 g/cm3, which is relatively high for organic compounds. Their lattice parameters are: Self-assembly and films Use The main industrial use of PTCDA is as a precursor to Rylene dye A rylene dye is a dye based on the rylene framework of naphthalene units linked in peri-positions. In homologues additional naphthalene units are added, forming compounds — or ''poly(peri-naphthalene)s'' — such as perylene, t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PTCDA AFM
Perylenetetracarboxylic dianhydride (PTCDA) is an organic dye molecule and an organic semiconductor. It is used as a precursor to a class of molecules known as Rylene dyes, which are useful as pigments and dyes. It is a dark red solid with low solubility in aromatic solvents. The compound has attracted much interest as an organic semiconductor. Structure PTCDA consists of a perylene core to which two anhydride groups have been attached, one at either side. It occurs in two crystalline forms, α and β. Both have the P21/c monoclinic In crystallography, the monoclinic crystal system is one of the seven crystal systems. A crystal system is described by three vectors. In the monoclinic system, the crystal is described by vectors of unequal lengths, as in the orthorhombic s ... symmetry and a density of ca. 1.7 g/cm3, which is relatively high for organic compounds. Their lattice parameters are: Self-assembly and films Use The main industrial use of PTCDA is as a p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PTCDA Self-assembly STM
Perylenetetracarboxylic dianhydride (PTCDA) is an organic dye molecule and an organic semiconductor. It is used as a precursor to a class of molecules known as Rylene dyes, which are useful as pigments and dyes. It is a dark red solid with low solubility in aromatic solvents. The compound has attracted much interest as an organic semiconductor. Structure PTCDA consists of a perylene core to which two anhydride groups have been attached, one at either side. It occurs in two crystalline forms, α and β. Both have the P21/c monoclinic symmetry and a density of ca. 1.7 g/cm3, which is relatively high for organic compounds. Their lattice parameters are: Self-assembly and films Use The main industrial use of PTCDA is as a precursor to Rylene dye A rylene dye is a dye based on the rylene framework of naphthalene units linked in peri-positions. In homologues additional naphthalene units are added, forming compounds — or ''poly(peri-naphthalene)s'' — such as perylene, t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rylene Dye
A rylene dye is a dye based on the rylene framework of naphthalene units linked in peri-positions. In homologues additional naphthalene units are added, forming compounds — or ''poly(peri-naphthalene)s'' — such as perylene, terrylene and quarterrylene. Perylene dyes Perylene dyes are useful for their intense visible light absorption, high stability, electron accepting ability, and unity quantum yields.Huang, C., Barlow,S., Marder, S. (2011), Perylene-3,4,9,10-tetracarboxylic Acid Diimides: Synthesis, Physical Properties, and Use in Organic Electronics. Journal of Organic Chemistry, 76, 2386–2407. Due to these properties, they are actively researched in academia for optoelectronic and photovoltaic devices, thermographic processes, energy-transfer cascades, light-emitting diodes, and near-infrared-absorbing systems.Weil, T., Vosch, T., Hofkens, J., Peneva, K. and Müllen, K. (2010),'' The Rylene Colorant Family—Tailored Nanoemitters for Photonics Research and Applicatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monoclinic
In crystallography, the monoclinic crystal system is one of the seven crystal systems. A crystal system is described by three vectors. In the monoclinic system, the crystal is described by vectors of unequal lengths, as in the orthorhombic system. They form a parallelogram prism. Hence two pairs of vectors are perpendicular (meet at right angles), while the third pair makes an angle other than 90°. Bravais lattices Two monoclinic Bravais lattices exist: the primitive monoclinic and the base-centered monoclinic. For the base-centered monoclinic lattice, the primitive cell has the shape of an oblique rhombic prism;See , row mC, column Primitive, where the cell parameters are given as a1 = a2, α = β it can be constructed because the two-dimensional centered rectangular base layer can also be described with primitive rhombic axes. Note that the length a of the primitive cell below equals \frac \sqrt of the conventional cell above. Crystal classes The table below org ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Compound
In chemistry, organic compounds are generally any chemical compounds that contain carbon-hydrogen or carbon-carbon bonds. Due to carbon's ability to catenate (form chains with other carbon atoms), millions of organic compounds are known. The study of the properties, reactions, and syntheses of organic compounds comprise the discipline known as organic chemistry. For historical reasons, a few classes of carbon-containing compounds (e.g., carbonate salts and cyanide salts), along with a few other exceptions (e.g., carbon dioxide, hydrogen cyanide), are not classified as organic compounds and are considered inorganic. Other than those just named, little consensus exists among chemists on precisely which carbon-containing compounds are excluded, making any rigorous definition of an organic compound elusive. Although organic compounds make up only a small percentage of Earth's crust, they are of central importance because all known life is based on organic compounds. Liv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Semiconductor
Organic semiconductors are solids whose building blocks are pi-bonded molecules or polymers made up by carbon and hydrogen atoms and – at times – heteroatoms such as nitrogen, sulfur and oxygen. They exist in the form of molecular crystals or amorphous thin films. In general, they are electrical insulators, but become semiconducting when charges are either injected from appropriate electrodes, upon doping or by photoexcitation. General properties In molecular crystals the energetic separation between the top of the valence band and the bottom conduction band, i.e. the band gap, is typically 2.5–4 eV, while in inorganic semiconductors the band gaps are typically 1–2 eV. This implies that they are, in fact, insulators rather than semiconductors in the conventional sense. They become semiconducting only when charge carriers are either injected from the electrodes or generated by intentional or unintentional doping. Charge carriers can also be generated in the c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pigments
A pigment is a colored material that is completely or nearly insoluble in water. In contrast, dyes are typically soluble, at least at some stage in their use. Generally dyes are often organic compounds whereas pigments are often inorganic compounds. Pigments of prehistoric and historic value include ochre, charcoal, and lapis lazuli. Economic impact In 2006, around 7.4 million tons of inorganic, organic, and special pigments were marketed worldwide. Estimated at around US$14.86 billion in 2018 and will rise at over 4.9% CAGR from 2019 to 2026. The global demand for pigments was roughly US$20.5 billion in 2009. According to an April 2018 report by ''Bloomberg Businessweek'', the estimated value of the pigment industry globally is $30 billion. The value of titanium dioxide – used to enhance the white brightness of many products – was placed at $13.2 billion per year, while the color Ferrari red is valued at $300 million each year. Physical principles Like ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Perylene
Perylene or perilene is a polycyclic aromatic hydrocarbon with the chemical formula C20H12, occurring as a brown solid. It or its derivatives may be carcinogenic, and it is considered to be a hazardous pollutant. In cell membrane cytochemistry, perylene is used as a fluorescent lipid probe. It is the parent compound of a class of rylene dyes. Reactions Like other polycyclic aromatic compounds, perylene is reduced by alkali metals to give a deeply colored radical anion and a dianion. The diglyme solvates of these salts have been characterized by X-ray crystallography. Emission Perylene displays blue fluorescence. It is used as a blue-emitting dopant material in OLEDs, either pure or substituted. Perylene can be also used as an organic photoconductor. It has an absorption maximum at 434 nm, and as with all polycyclic aromatic compounds, low water solubility (1.2 x 10−5 mmol/L). Perylene has a molar absorptivity of 38,500 M−1cm−1 at 435.7 nm. Image:Peryle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Acid Anhydride
An organic acid anhydride is an acid anhydride that is an organic compound. An acid anhydride is a compound that has two acyl groups bonded to the same oxygen atom. A common type of organic acid anhydride is a carboxylic anhydride, where the parent acid is a carboxylic acid, the formula of the anhydride being (RC(O))2O. Symmetrical acid anhydrides of this type are named by replacing the word ''acid'' in the name of the parent carboxylic acid by the word ''anhydride''. Thus, (CH3CO)2O is called ''acetic anhydride.'' Mixed (or unsymmetrical) acid anhydrides, such as acetic formic anhydride (see below), are known, whereby reaction occurs between two different carboxylic acids. Nomenclature of unsymmetrical acid anhydrides list the names of both of the reacted carboxylic acids before the word "anhydride" (for example, the dehydration reaction between benzoic acid and propanoic acid would yield "benzoic propanoic anhydride"). One or both acyl groups of an acid anhydride may also be d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monoclinic
In crystallography, the monoclinic crystal system is one of the seven crystal systems. A crystal system is described by three vectors. In the monoclinic system, the crystal is described by vectors of unequal lengths, as in the orthorhombic system. They form a parallelogram prism. Hence two pairs of vectors are perpendicular (meet at right angles), while the third pair makes an angle other than 90°. Bravais lattices Two monoclinic Bravais lattices exist: the primitive monoclinic and the base-centered monoclinic. For the base-centered monoclinic lattice, the primitive cell has the shape of an oblique rhombic prism;See , row mC, column Primitive, where the cell parameters are given as a1 = a2, α = β it can be constructed because the two-dimensional centered rectangular base layer can also be described with primitive rhombic axes. Note that the length a of the primitive cell below equals \frac \sqrt of the conventional cell above. Crystal classes The table below org ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Perylene Dyes
Perylene or perilene is a polycyclic aromatic hydrocarbon with the chemical formula C20H12, occurring as a brown solid. It or its derivatives may be carcinogenic, and it is considered to be a hazardous pollutant. In cell membrane cytochemistry, perylene is used as a fluorescent lipid probe. It is the parent compound of a class of rylene dyes. Reactions Like other polycyclic aromatic compounds, perylene is reduced by alkali metals to give a deeply colored radical anion and a dianion. The diglyme solvates of these salts have been characterized by X-ray crystallography. Emission Perylene displays blue fluorescence. It is used as a blue-emitting dopant material in OLEDs, either pure or substituted. Perylene can be also used as an organic photoconductor. It has an absorption maximum at 434 nm, and as with all polycyclic aromatic compounds, low water solubility (1.2 x 10−5 mmol/L). Perylene has a molar absorptivity of 38,500 M−1cm−1 at 435.7 nm. Image:Peryl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vat Dyes
A value-added tax (VAT), known in some countries as a goods and services tax (GST), is a type of tax that is assessed incrementally. It is levied on the price of a product or service at each stage of production, distribution, or sale to the end consumer. If the ultimate consumer is a business that collects and pays to the government VAT on its products or services, it can reclaim the tax paid. It is similar to, and is often compared with, a sales tax. VAT is an indirect tax because the person who ultimately bears the burden of the tax is not necessarily the same person as the one who pays the tax to the tax authorities. Not all localities require VAT to be charged, and exports are often exempt. VAT is usually implemented as a destination-based tax, where the tax rate is based on the location of the consumer and applied to the sales price. The terms VAT, GST, and the more general consumption tax are sometimes used interchangeably. VAT raises about a fifth of total tax revenues b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
