Crystal violet chemical structure

Although treated as separate classes in the Colour Index, these structural types are closely related and the few diphenylmethane dyes such as auramine (1.28 Cl Basic Yellow 2) are now of little practical interest. Commercial usage of the triarylmethane dyes and pigments has also declined considerably in favour of the major chemical classes. They were formerly noteworthy contributors to the acid, basic, mordant and solvent ranges, primarily in the violet, blue and green sectors. Numerous structural examples are recorded in the Colour Index. The terminal groupings can be amine/quinonimine, as in auramine and crystal violet (1.29 Cl Basic Violet 3), hydroxy/quinone, or both. The aryl nuclei are not always benzenoid (section 6.5). 

TLC coupled with mass spectrometry employing desorption electrospray ionization has been used for the separation of synthetic dyes. The chemical structures of dyes included in the investigation are shown in Fig. 3.7. ODS HPTLC plates (10 X 10 cm) were used as the stationary phase the mobile phase consisted of methanol-tetrahydrofuran (60 40, v/v) containing 50-100 mM ammonium acetate for the positive-ion test and of methanol-water (70 30, v/v) for the negative-ion test. Test mixtures for negative- and positive-ion mode detection consisted of methyleneblue, crystal violet, rhodamine 6G... 

The thickness and chemical composition of the cell wall and its adjacent structures determine how avidly a cell wall takes up and/or retains specific dyes. Most cells can be differentiated on the basis of whether they retain crystal violet stain during the Gram stain procedure. Those that can retain the dye, called Gram positive, do so because their cell walls consist of a thick peptidoglycan layer. In contrast, Gram-negative cells possess a thin peptidoglycan layer. Often... 

Chemical Structure It is a mixture of V-pentamethyl (as shown) and V-hexamethyl (which is Crystal Violet) p-rosaniline chlorides... 

Using one of the references for finding chemical structures presented in the previous chapter, locate the structure of gentian violet, also called crystal violet. This dye is a widely used biological stain. 

FIGURE 6 Chemical structure of crystal violet cation. 

POTASSIUM. [CAS 7440-09-7]. Chemical element, symbol K, at, no. 19, at. wt. 39.098, periodic table group 1 (alkali metals i, mp 63,3cC, bp 760°C. density 0.86 g/cm3 (20°C). Elemental potassium has a body-centered cubic crystal structure. Potassium is a silver-white metal, can be readily molded, and cut by a knife, oxidizes instantly on exposure to air, and reacts violently with H2O, yielding potassium hydroxide and hydrogen gas, which burns spontaneously in air with a violet flame due to volatilized potassium element, is preserved under kerosene, burns in air at a red heat with a violet flame. Discovered by Davy in 1807. 

Crystal structure In certain cases, chemically identical pigments existing in different crystal forms (also known as polymorphisms) may exhibit a different hue. Pigments that clearly show the effect of polymorphism on hue are quinacridone pigment (Pigment Violet 19), phthalocyanine pigment (Pigment Blue 15) and lead chromates. 

Figure 66 Crystal structure of 68a, 68b, 68c, 68d, and 68e showing structural transformations on desolvation and moisture coordination. Ball color gray, zinc green, fluorine blue, nitrogen red, oxygen violet in 68e, coordinated water. Noncoordinated guest molecules and hydrogen atoms are omitted for clarity. Coordination environments of the zinc cluster (a) and views of the single framework along the i-axis (b). (Reprinted with permission from Ref 85. Copyright (2011) American Chemical Society.)...

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