Fluorescence Fluoride

The procedure utilises eriochrome blue black RC (also called pontachrome blue black R Colour Index No. 15705) at a pH of 4,8 in a buffer solution. Beryllium gives no fluorescence and does not interfere iron, chromium, copper, nickel, and cobalt mask the fluorescence fluoride must be removed if present. The method may be adapted for the determination of aluminium in steel. 

Arimori, S., Davidson, M. G., Fyles, T. M., Hibbert, T. G., James, T. D., Kociok-Kohn, G. I., Synthesis and structural characterisation of the first bis(bora)calixarene a selective, bidentate, fluorescent fluoride sensor. Chem. Commun. 2004, 1640-1641. 

A series of multifunctional anthrylboranes with up to six boron centers and divergently extended itt-conjugation have been reported. Trianthrylborane itself is bright orange, whereas the extended system (157) is dark red colored. This bathochromic shift was attributed to the more extended delocalization in the starbust oligomer (157). Two reversible reduction waves were found for the two different boron environments in (157). The anthrylboranes have also been studied as fluorescent fluoride sensors (see Section 7.2.1). 

Liu, Z.Q., Shi, M., Li, F.Y., etal. (2005) Highly selective two-photon fluorescent fluoride sensor derived from organic boranes. Organic Letters, 7, 5481-5484. 

Borax beads containing uranium exhibit an appreciable green fluorescence. Fluoride beads of the alkalis and alkaline earth metals fluoresce especially well. Sodium fluoride beads light up to a deep yellow color and are most striking. They can be used to detect uranium. 

Zhou, J., Li, H. Highly Fluorescent Fluoride-Responsive Hydrogels Embedded with CdTe Quantum Dots. ACS Appl. Mater. Interfaces 4(2), 721-724 (2012)... 

Figure 8.28 shows how the X-rays fall on the solid or liquid sample which then emits X-ray fluorescence in the region 0.2-20 A. The fluorescence is dispersed by a flat crystal, often of lithium fluoride, which acts as a diffraction grating (rather like the quartz crystal in the X-ray monochromator in Figure 8.3). The fluorescence may be detected by a scintillation counter, a semiconductor detector or a gas flow proportional detector in which the X-rays ionize a gas such as argon and the resulting ions are counted.

Nickel fluoride is used in marking ink compositions (see Inks), for fluorescent lamps (4) as a catalyst in transhalogenation of fluoroolefins (5), in the manufacture of varistors (6), as a catalyst for hydrofluorination (7), in the synthesis of XeF (8), and in the preparation of high purity elemental fluorine for research (9) and for chemical lasers (qv) (10). 

Fluorescent brightening agents, 1, 338-341 Fluoride ions nucleophilicity crown ethers and, 7, 756 Fluorides synthesis... 

Research Opportunities. The presence of a long-lived fluorescing state following either 532 nm or 1064 nm excitation of PuF6(g) provides a valuable opportunity to study the extent to which electronic energy in a 5f electron state is available in photochemical and energy transfer reactions. Such gas phase bimolecular reactions would occur in a weak interaction limit governed by van der Waals forces. Seen from the perspective of potential photochemical separations in fluoride volatility... 

The blue fluorescence of dioxetane 25 (X = O and CH2, R = alkyl) in the presence of fluoride ion has been studied <96TL5939>. 

Koskela SJM, Fyles TM, James TD (2005) A ditopic fluorescent sensor for potassium fluoride. Chem Commun 7 945-947... 

Direct visualization of femtosecond filamentation is crucial to understanding the phenomenon. As the energy of a single infrared photon is much too small to effect an electronic transition, one has to take recourse to multiphoton absorption induced fluorescence to come up with a scheme to directly visualize filamentation in condensed media. One such scheme that has been successfully implemented involves the use of a crystal of barium fluoride, a material that is known to be very good scintillator [38]. 

Fig. 2 Chemical structures of fluorescent ligands (anion coordination sites are indicated in blue) and tentative reaction schemes on interaction of 6 with chloride and fluoride in dichloromethane according to the color patterns observed in [41]. The wavelengths of absorption given in brackets have been calculated for the geometry optimized species 6, 6-C1 and 6 in the gas phase by semiempirical AMI calculations (Ampac V6.55, Semichem)...

Kim TH, Swager TM (2003) A fluorescent self-amplifying wavelength-responsive sensory polymer for fluoride ions. Angew Chem Int Ed 42 4803 1806... 

Zhou G, Cheng Y, Wang L, Jing X, Wang F (2005) Novel polyphenylenes containing phenol-substituted oxadiazole moieties as fluorescent chemosensors for fluoride ion. Macromolecules 38 2148-2153... 

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