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Charge-transfer complexities

M.p. 296 C. Accepts an electron from suitable donors forming a radical anion. Used for colorimetric determination of free radical precursors, replacement of Mn02 in aluminium solid electrolytic capacitors, construction of heat-sensitive resistors and ion-specific electrodes and for inducing radical polymerizations. The charge transfer complexes it forms with certain donors behave electrically like metals with anisotropic conductivity. Like tetracyanoethylene it belongs to a class of compounds called rr-acids. tetracyclines An important group of antibiotics isolated from Streptomyces spp., having structures based on a naphthacene skeleton. Tetracycline, the parent compound, has the structure ... [Pg.389]

Its charge transfer complexes with aromatic hydrocarbons have characteristic melting points and may be used for the identification and purification of the hydrocarbons. [Pg.406]

As well as the cr-complexes discussed above, aromatic molecules combine with such compounds as quinones, polynitro-aromatics and tetra-cyanoethylene to give more loosely bound structures called charge-transfer complexes. Closely related to these, but usually known as Tt-complexes, are the associations formed by aromatic compounds and halogens, hydrogen halides, silver ions and other electrophiles. [Pg.117]

Arylthiazoles derivatives are good subjects for the study of these transfers. Thus the absorption wavelengths and the enthalpies of formation of a series of charge-transfer complexes of the type arylthiazole-TCNE, have been determined (147). The results are given in Table IIM3. [Pg.354]

Charge-transfer absorption is important because it produces very large absorbances, providing for a much more sensitive analytical method. One important example of a charge-transfer complex is that of o-phenanthroline with Fe +, the UV/Vis spectrum for which is shown in Figure 10.17. Charge-transfer absorption in which the electron moves from the ligand to the metal also is possible. [Pg.382]

Furan and maleic anhydride undergo the Diels-Alder reaction to form the tricycHc 1 1 adduct, 7-oxabicyclo [2.2.1]hept-5-ene-2,3-dicarboxyHc anhydride (4) in exceUent yield. Other strong dienophiles also add to furan (88). Although both endo and exo isomers are formed initially, the former rapidly isomerize to the latter in solution, even at room temperature. The existence of a charge-transfer complex in the system has been demonstrated (89,90). [Pg.81]

The first quantitative model, which appeared in 1971, also accounted for possible charge-transfer complex formation (45). Deviation from the terminal model for bulk polymerization was shown to be due to antepenultimate effects (46). Mote recent work with numerical computation and C-nmr spectroscopy data on SAN sequence distributions indicates that the penultimate model is the most appropriate for bulk SAN copolymerization (47,48). A kinetic model for azeotropic SAN copolymerization in toluene has been developed that successfully predicts conversion, rate, and average molecular weight for conversions up to 50% (49). [Pg.193]

Intense sodium D-line emission results from excited sodium atoms produced in a highly exothermic step (175). Many gas-phase reactions of the alkafl metals are chemiluminescent, in part because their low ioni2ation potentials favor electron transfer to produce intermediate charge-transfer complexes such as [Ck Na 2] (1 )- There appears to be an analogy with solution-phase electron-transfer chemiluminescence in such reactions. [Pg.270]

Other miscellaneous applications of malononitdle are the synthesis of 7,7,8,8-tetracyanoquinodimethane (46) which is a powerful electron acceptor in the formation of charge-transfer complexes which are of interest because of their conductivity of electricity (96), as well as of 2-chloroben2yhdene malononitnle [2698-41-1] (45) also known as CS-gas, which is a safe lachrymatory chemical used for self-defense devices (97). [Pg.475]

The dipole moment varies according to the solvent it is ca 5.14 x 10 ° Cm (ca 1.55 D) when pure and ca 6.0 x 10 ° Cm (ca 1.8 D) in a nonpolar solvent, such as benzene or cyclohexane (14,15). In solvents to which it can hydrogen bond, the dipole moment may be much higher. The dipole is directed toward the ring from a positive nitrogen atom, whereas the saturated nonaromatic analogue pyrroHdine [123-75-1] has a dipole moment of 5.24 X 10 ° C-m (1.57 D) and is oppositely directed. Pyrrole and its alkyl derivatives are TT-electron rich and form colored charge-transfer complexes with acceptor molecules, eg, iodine and tetracyanoethylene (16). [Pg.354]

Although most nonionic organic chemicals are subject to low energy bonding mechanisms, sorption of phenyl- and other substituted-urea pesticides such as diuron to sod or sod components has been attributed to a variety of mechanisms, depending on the sorbent. The mechanisms include hydrophobic interactions, cation bridging, van der Waals forces, and charge-transfer complexes. [Pg.221]

Charge-transfer complexes occur with cyanogen iodide, tetracyanoethylene, and oxygen (63—65). [Pg.110]

Li-I 2 Li + I2 2 Lil 2.8 0.9 290 soHd electrolyte, 10+ year life welded constmction, used in most of heart pacers, iodine charge transfer complex Medtronic Catalyst WUson Greatbatch... [Pg.516]

Charge-Transfer Compounds. Similat to iodine and chlorine, bromine can form charge-transfer complexes with organic molecules that can serve as Lewis bases. The frequency of the iatense uv charge-transfer adsorption band is dependent on the ionization potential of the donor solvent molecule. Electronic charge can be transferred from a TT-electron system as ia the case of aromatic compounds or from lone-pairs of electrons as ia ethers and amines. [Pg.284]

The bis(diene) (46) adds dienophiles preferentially on the side syn to the oxirane moiety (Scheme 35) (80X149). This may be due to formation of a charge-transfer complex by donation of electron density from oxygen into an antibonding orbital on the dienophile. [Pg.107]


See other pages where Charge-transfer complexities is mentioned: [Pg.89]    [Pg.170]    [Pg.313]    [Pg.406]    [Pg.552]    [Pg.1613]    [Pg.121]    [Pg.226]    [Pg.337]    [Pg.63]    [Pg.237]    [Pg.238]    [Pg.246]    [Pg.246]    [Pg.246]    [Pg.473]    [Pg.367]    [Pg.263]    [Pg.270]    [Pg.270]    [Pg.407]    [Pg.189]    [Pg.220]    [Pg.518]    [Pg.535]    [Pg.433]    [Pg.132]    [Pg.132]    [Pg.144]    [Pg.148]    [Pg.510]    [Pg.557]    [Pg.618]   
See also in sourсe #XX -- [ Pg.361 ]




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1.3.5- Trinitrobenzene, charge-transfer complexes

Anilines charge-transfer complexes

Arenes charge-transfer complexes

Aromatic charge transfer complexes

Aromatic substitution reactions, role charge-transfer complexes

Azines charge-transfer complexes

Azulenes charge transfer complexes

Benzene-iodine complex, charge-transfer

Benzene-iodine complex, charge-transfer reaction

Binuclear complex charge transfer spectra

Block Copolymers from charge transfer complexes

Bromine-olefin charge transfer complexes as essential intermediates in bromination

Carbon dioxide Charge-transfer complexes

Charge transfer and other donor---acceptor PLC complexes

Charge transfer complex (CTC

Charge transfer complex electric conductivity

Charge transfer complex matrix

Charge transfer complex mechanical properties

Charge transfer complex, solid state

Charge transfer complexes between

Charge transfer complexes constants

Charge transfer complexes from electrophilic

Charge transfer complexes group

Charge transfer complexes luminescent spectra

Charge transfer complexes monomers

Charge transfer complexes olefins

Charge transfer complexes polymerization

Charge transfer complexes spectra

Charge transfer complexes spectra! features

Charge transfer complexes theory

Charge transfer complexes thermodynamics

Charge transfer complexes viologens

Charge transfer complexes with fullerenes

Charge transfer complexes with halogens

Charge transfer complexes, biological

Charge transfer complexes, biological electron donor-acceptor

Charge transfer complexes, biological examples

Charge transfer complexes, biological stability

Charge transfer complexes, biological systems

Charge transfer complexes, titration

Charge transfer dithiolene-diimine complexes

Charge transfer dithiolene-donor complexes

Charge transfer gold complexes

Charge transfer in endohedral complexes

Charge transfer iron complexes

Charge transfer ruthenium complexes

Charge transfer transitions cobalt complexes

Charge transfer transitions complexes

Charge transfer, bonding complexes

Charge transfer, metal-carbonyl complexes

Charge transfer, radical complex

Charge-Transfer Complexes of Polyalkylated Ferrocenes

Charge-Transfer Excited States of Transition Metal Complexes

Charge-transfer (CT) complexes

Charge-transfer absorption band complexes

Charge-transfer complex 424 Subject

Charge-transfer complex comonomers

Charge-transfer complex formation and

Charge-transfer complex of TTF

Charge-transfer complex participation

Charge-transfer complex, photoluminescence

Charge-transfer complexes and radical ion salts

Charge-transfer complexes chlorination

Charge-transfer complexes from

Charge-transfer complexes from tetracyanobenzenes

Charge-transfer complexes from tetracyanoethylene

Charge-transfer complexes from tetracyanoquinodimethane

Charge-transfer complexes of ferrocene

Charge-transfer complexes of halogens

Charge-transfer complexes polyimides

Charge-transfer complexes polymer-oxygen

Charge-transfer complexes polystyrene

Charge-transfer complexes pyridine-halogen

Charge-transfer complexes reversible ionization

Charge-transfer complexes solvent photochemistry

Charge-transfer complexes tetrahydrofurane

Charge-transfer complexes triplet excitons

Charge-transfer complexes with other organic systems

Charge-transfer complexes with various organic

Charge-transfer complexes with various organic acceptors

Charge-transfer complexes, formation

Charge-transfer complexes, in organic

Charge-transfer complexes, work term

Charge-transfer complexes/interaction

Charge-transfer complexing

Charge-transfer complexing lone pair

Charge-transfer donor-acceptor complexes

Charge-transfer oxygen-polystyrene complexes

Charge-transfer transitions metal-carbonyl complexes

Chromium complexes charge-transfer transitions

Cobalt complex charge-transfer process

Cobalt complexes, absorption charge transfer transitions

Colours charge transfer complexes

Complex charge

Complex charge-transfer

Complex charge-transfer

Complex impedance spectroscopy charge transfer kinetics

Complexation charge-transfer

Complexes, alkyne-metal charge transfer

Conductivity charge-transfer complex-based

Contact charge transfer complexes

Copper charge-transfer complexes

Donor-acceptor complex Charge-transfer complexes

Electron Affinities and Charge Transfer Complex Energies

Electron Affinities of Charge Transfer Complex Acceptors

Electron paramagnetic resonance charge-transfer complex

Encounter complex charge-transfer interactions

Exciplexes, Electron Donor-Acceptor Complexes, and Related Charge-transfer Phenomena

Excited radical, charge transfer complex

Ferrocene charge transfer complexes

General Spectral Features of Charge Transfer Complexes

Ground-state charge-transfer complexes

Group 17 elements charge-transfer complexes

Halide complexes charge transfer spectra

Halogens charge-transfer complexes

Hydrogen Bonding and Charge-Transfer Complexing

INDEX charge-transfer complexes

Impurity charge-transfer complexes

Initiation charge-transfer complexes

Intraligand charge transfer complexes

Intramolecular charge-transfer complexes

Iodine charge-transfer complexes

Iodine-containing charge transfer complexes

Iron -1,10-phenanthroline complex charge transfer

Iron complexes charge transfer transitions

Irradiation of Charge-Transfer Complexes

Langmuir-Blodgett films charge-transfer complexes

Ligand-metal charge transfer complexes

Ligand-to-metal charge transfer d complexes

Methyl complexes, charge transfer spectra

Mulliken charge-transfer complex

Mulliken relationship charge-transfer complex absorption

Octahedral complexes charge transfer absorption

Oxygen charge-transfer complexes with

Oxygen with poly charge-transfer complexes

Paraquat charge-transfer complexes

Penultimate Effects and Charge-Transfer Complexes

Phenol complex with iron, charge transfer

Phenothiazines charge-transfer complexes

Poly charge-transfer complexes

Polyene charge transfer complexes between

Ruthenium complex charge-transfer process

Ruthenium complexes charge transfer transitions

Solutions and charge-transfer complexes

Spectra of charge transfer complexes

Square-planar complexes charge transfer

Strong charge-transfer complexes

Structural Alignment in Charge Transfer Complexes

Sulfur complexes, charge-transfer bands

Supramolecular Charge Transfer Complexes

Tetracyanoethene, charge-transfer complex

Theory of Charge Transfer Complexes

Thermodynamics of Charge Transfer Complexes

Titanium complexes charge-transfer spectra

Transition metal complexes charge-transfer transitions

Weak charge-transfer complex crystals

Zeolites charge-transfer complex with oxygen

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