Charge characteristics

A great number of monoaza or polyaza. either symmetrica] or unsym-metrical, mono trimethine thiazolocyainines have been synthesized in order to verify or to obtain semiempirical rules, more or less based on the resonance theory, concerning the relation between the color of a thiazolo dye and the number and place of nitrogen atoms in the chromophoric chain. For example. Forster s rule applies to ionic dyes and stipulates that the will increase with the decreasing tendency of chromophoric atoms lying between the two auxochromes to take up the characteristic charges (90). 

Now that we know how to name the cations and anions, we merely have to put the two names together to get the names of ionic compounds. The cation is named first and the anion is named next. The number of cations and anions per formula unit need not be included in the name of the compound because anions have characteristic charges, and the charge on the cation has already been established by its name. There are as many cations and anions as needed to get a neutral compound with the lowest possible subscripts. 

Bicumene readily forms a highly colored charge-transfer complex with nitro-sonium (NO+) cation that can be isolated as a crystalline salt.194 Thus, a solution of bicumene and NO+SbClcharge-transfer bands with A = 338 and 420 nm that are indistinguishable from those of the nitrosonium complexes with other methylbenzenes (equation 62). 

In these equations, the following characteristic charges have been defined ... 

The halogens all tend to gain one electron, giving their ions a characteristic charge of-1. The alkali metals, on the other side of the periodic table, all readily lose one electron, so their ions possess a charge of + 1. Charges are balanced in a compound with the number of alkali metal ions equal... 

Electronic spectra Cu1—colourless Cu11—normal d-d Cu1—colourless Cu11—near normal d-d. Characteristic (I)-(II) charge transfer spectra No spectra of constituent Cu1 and Cu11 ions. Characteristic charge transfer spectra. Metallic reflectivity... 

If E. coli is grown in a cadmium-containing, zinc-deficient medium, the enzyme is found to be active, but to contain six Cd2+ per molecule. The presence of cysteinyl ligands is confirmed by the observation of the characteristic charge-transfer bands. The binding of substrate perturbs the absorption and CD spectra of the zinc and cadmium enzymes, and the d-d spectrum of the nickel enzyme, showing that "the conformation of the R subunit is affected by the binding of substrate to the C subunit.530,531... 

A photoprocess rather common with inorganic compounds is the formation of solvated electrons, e [ in organic solvents and eat in aqueous solutions.43,44 The photoprocess is most commonly observed with anions whose absorption spectrum exhibits a characteristic charge transfer to solvent, CTTS, band in the ultraviolet. It is the typical photoprocess of the halide anions shown in Equations 6.89 and 6.90 where X = Cl, Br, and I-. 

The ions which are preferentially adsorbed by the sol particles, are held in the fixed part of the double layer. It is these ions which give the characteristic charge to the sol particles. 

Marcus (92) elaborated the continuum theory by separating the polarization of the dielectric into two superimposed polarizations the "nonequilibrium polarization, and the "equilibrium polarization. In the precursor complexp there is a characteristic charge distribution giving a field Ecp, and both polarizations are at equilibrium. When the photon is absorbed the charge distribution rapidly changes to a new value with an associated field Et. The nonequilibrium polarization remains at its old value, but the equilibrium polarization changes to a new value, jointly determined by the charges and the nonequilibrium polarization. 

Characteristic charge distribution of native or denaturated protein. 

The second group of semiempirical MO LCAO methods is constituted by zero-differential overlap methods (9). Two subgroups can be specified here which somewhat conventionally may be called physical and chemical. The former involves CNDO/2, INDO, and some of their modifications, for example, CNDO/S. These methods are directed to the calculations of the electron characteristics charge distributions, dipole moments, polarizabili-... 

Chains, Stokes law with, 68-70 Chan, T., 120 Chapman, S. J., 168-169 Characteristic charge, 187 Characteristic length and diffusion, 155 Charging mechanisms, 179 collisions with ions, 185 contact electrification, 182-183 corona discharge, 195-198 diffusion, 185-189,195 electric, 179-183 equilibrium with, 200-201 steady-state theory of, 201-207 transient approach to, 207-208 field charging, 185,189-195 flame ionization, 184-185 and force, 179-180 frictional, 184... 

Most main group cations and all monatomic anions have characteristic charges that are easy to learn, so in their compounds with other ions, the charges on the other ions are easy to deduce. 

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