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Charge local

RAMSES is usually generated from molecular structures in a VB representation. The details of the connection table (localized charges, lone pairs, and bond orders) are kept within the model and are accessible for further processes. Bond orders are stored with the n-systems, while the number of free electrons is stored with the atoms. Upon modification oF a molecule (e.g., in systems dealing with reactions), the VB representation has to be generated in an adapted Form from the RAMSES notation. [Pg.69]

Dyeing Mechanism. The original basic dyes were characterized by a delocalized charge in the molecule. As the importance of acryHc fibers grew basic dyes were developed with localized charge in one specific part of the molecule allowing stronger salt links to be formed than with the delocalized type. [Pg.362]

Relationships connecting stmcture and properties of primary alkylamines of normal stmcture C, -C gin chloroform and other solvents with their ability to extract Rh(III) and Ru(III) HCA from chloride solutions have been studied. The out-sphere mechanism of extraction and composition of extracted associates has been ascertained by UV-VIS-, IR-, and H-NMR spectroscopy, saturation method, and analysis of organic phase. Tertiary alkylamines i.e. tri-n-octylamine, tribenzylamine do not extract Ru(III) and Rh(III) HCA. The decrease of radical volume of tertiary alkylamines by changing of two alkyl radicals to methyl make it possible to diminish steric effects and to use tertiary alkylamines with different radicals such as dimethyl-n-dodecylamine which has not been used previously for the extraction of Rh(III), Ru(III) HCA with localized charge. [Pg.257]

Polar interactions can occur when a molecule contains a dipole or a number of dipoles which take the form of localized charges situated on different parts of the molecule. Each charge has an equal and opposite charge situated elsewhere on the molecule and, thus, the molecule has no net charge associated with it. Interactions occur between the charges on different molecules but are always accompanied by dispersive... [Pg.65]

Hays measured the current associated with electrically charged 99 p.m diameter particles of styrene divinylbenzene particles as these particles traversed gaps of 520 and 137 p.m separating two parallel electrodes. Based on these results. Hays [81 ] argued for the existence of locally charged patches on the particles. [Pg.167]

Tlie suffices i and J refer to individual atoms and S and Sj to the species of the atoms involved. The summation over j extends over those neighbors of the atom i for which ry, the separation of atoms i and J, is within the cutoff radii of these potentials. The second term in Equation (la) is the attractive many-body term and both V and are empirically fitted pair potentials. A Justification for the square root form of the many-body function is provided in the framework of a second moment approximation of the density of states to the tight-binding theory incorporating local charge conservation in this framework the potentials represent squares of the hopping integrals (Ackland, et al. 1988). [Pg.357]

In the perfect lattice the dominant feature of the electron distribution is the formation of the covalent, directional bond between Ti atoms produced by the electrons associated with d-orbitals. The concentration of charge between adjacent A1 atoms corresponds to p and py electrons, but these electrons are spatially more dispersed than the d-electrons between titanium atoms. Significantly, there is no indication of a localized charge build-up between adjacent Ti and A1 atoms (Fu and Yoo 1990 Woodward, et al. 1991 Song, et al. 1994). The charge densities in (110) planes are shown in Fig. 7a and b for the structures relaxed using the Finnis-Sinclair type potentials and the full-potential LMTO method, respectively. [Pg.366]

The activity of counterions whatever is the valency is imposed by the local charge parameter (X.) few experimental data were discussed previously [40, 41]. [Pg.26]

The pK (a) is directly related with the effective local charge density one can write... [Pg.27]

Experimental observations,23 supported by high-level ab initio calculations, 24 indicate that two extreme resonance forms contribute to the general energy of the benzyl cation the aromatic form A, in which the positive charge is concentrated at the methylene group, and the nonaromatic, methylene arenium form B with a sp2 ipso-carbon atom and ring-localized charge (Scheme 3.13). Unlike benzyl cations of the form A, which were isolated and studied, especially by Olah and coworkers,23 compounds represented by the form B remained elusive. Thus, metal complexation... [Pg.76]

The required local charge balance between cations and anions which is expressed in Pauling s rule causes the distribution of cations and anions among the octahedral and tetrahedral interstices of the sphere packing. Other distributions of the cations are not compatible with Pauling s rule. [Pg.210]

Figure 7.3 Truncated representation of p versus the distance from the nucleus for a spherically symmetric electron density of a free sulfur atom (3P). (b) Truncated representation of L(r) at the same scale as (a). This function reveals the three shells K, L, and M constituting the sulfur atom. Each shell consists of a region of local charge concentration (dark areas) and a region of local charge depletion (light... Figure 7.3 Truncated representation of p versus the distance from the nucleus for a spherically symmetric electron density of a free sulfur atom (3P). (b) Truncated representation of L(r) at the same scale as (a). This function reveals the three shells K, L, and M constituting the sulfur atom. Each shell consists of a region of local charge concentration (dark areas) and a region of local charge depletion (light...
The relative importance of the two mechanisms - the non-local electromagnetic (EM) theory and the local charge transfer (CT) theory - remains a source of considerable discussion. It is generally considered that large-scale rough surfaces, e.g. gratings, islands, metallic spheres etc., favour the EM theory. In contrast, the CT mechanism requires chemisorption of the adsorbate at special atomic scale (e.g. adatom) sites on the metal surface, resulting in a metal/adsorbate CT complex. In addition, considerably enhanced Raman spectra have been obtained from surfaces prepared in such a way as to deliberately exclude one or the other mechanism. [Pg.118]


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See also in sourсe #XX -- [ Pg.9 , Pg.29 ]




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Anionic SN2 Reactions Involving Charge-localized Anions

Cationic with Localized Charge

Charge change localization

Charge density local

Charge localization/delocalization

Charge-localization

Charge-localization

Charge-localized and -delocalized Valence Tautomeric Forms of Cyclic Oxocarbon Dianions

Charge-localized anions

Charge-localized ligands

Charged particles local equilibrium

Charges localized

Charges localized

Dyes with Localized Charge

Electronic charge density local maxima

Formal local charge

Induced charge localization

Local Density of States and Atomic Charges

Local charge concentrations and partial localization of the Fermi hole

Local charge neutrality

Local electric charge density

Local electric charge density potential

Local space charge neutrality

Localized charge distribution , theory

Locally Redistributing Charge

Redox potential local charges

Space charge limited currents localized states

The Concept of Charge and Unpaired Electron Localization

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