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Density functional approach calculations

The reason for this difference is very simple. It is that the density functional approach calculates the rate for the adiabatic channel. For AG x> this will proceed via an activated complex with successor-state formal electron density parameter A = 1 for AGq <-x, it will proceed via an activated... [Pg.304]

Wesolowski T A and Warshel A 1993 Frozen density functional approach to ah initio calculations of solvated molecules J. Phys. Chem. 97 8050... [Pg.2237]

Another approach to calculating molecular geometry and energy is based on density functional theory (DFT). DFT focuses on the electron cloud corresponding to a molecule. The energy of a molecule is uniquely specified by the electron density functional. The calculation involves the construction of an expression for the electron density. The energy of the system is then expressed as... [Pg.59]

We have extended the linear combination of Gaussian-type orbitals local-density functional approach to calculate the total energies and electronic structures of helical chain polymers[35]. This method was originally developed for molecular systems[36-40], and extended to two-dimensionally periodic sys-tems[41,42] and chain polymers[34j. The one-electron wavefunctions here are constructed from a linear combination of Bloch functions c>>, which are in turn constructed from a linear combination of nuclear-centered Gaussian-type orbitals Xylr) (in ihis case, products of Gaussians and the real solid spherical harmonics). The one-electron density matrix is given by... [Pg.42]

Seifert, G., Kruger, K., 1995, Density Functional Theory, Calculations of Potential Energy Surfaces and Reaction Paths in The Reaction Path in Chemistry Current Approaches and Perspectives, Heidrich, D. (ed.), Kluwer, Amsterdam. [Pg.300]

With the addition of a pseudopotential interaction between electrons and metal ions, the density-functional approach has been used82 to calculate the effect of the solvent of the electrolyte phase on the potential difference across the surface of a liquid metal. The solvent is modeled as a repulsive barrier or as a region of dielectric constant greater than unity or both. Assuming no specific adsorption, the metal is supposed to be in contact with a monolayer of water, modeled as a region of 3-A thickness (diameter of a water molecule) in which the dielectric constant is 6 (high-frequency value, appropriate for nonorientable dipoles). Beyond this monolayer, the dielectric constant is assumed to take on the bulk liquid value of 78, although the calculations showed that the dielectric constant outside of the monolayer had only a small effect on the electronic profile. [Pg.60]

Wesolowski, T. A. and A. Warshel. 1993. Frozen Density Functional Approach for ab initio Calculations of Solvated Molecules. [Pg.130]

Quantum mechanical approaches have been successfully used to predict hydrogen abstraction potentials and likely sites of metabolism of drug molecules [78-81]. AMI, Fukui functions, and density functional theory calculations could identify potential sites of metabolism. Activation energies for hydrogen abstraction were calculated by Olsen et al. [81] to be below 80 kj/mol, suggesting most CH groups can be metabolized which particular one depends on steric accessibility and intrinsic reactivities. [Pg.463]

Wesolowski, T. A. and Warshel, A. Frozen density functional approach for ab initio calculations of solvated molecules, J.Phys.Chem., 97 (1993), 8050-8053... [Pg.352]

Haworth, D. C. and S. H. El Tahry (1991). Probability density function approach for multidimensional turbulent flow calculations with application to in-cylinder flows in reciprocating engines. AIAA Journal 29, 208-218. [Pg.414]

A pseudo potential approach was adopted by Hickman et al. [259] to calculate the excited metastable states of a He atom under liquid He. The density functional approach developed by Dupont-Roc et al. [260] was applied subsequently [261] for the description of the nature of the cavity formed around an alkali atom in the excited state of non-zero angular momentum. The resulting form of the cavity differs very much from the spherical shape. A similar approach was adopted by De Toffol et al. [262] to find qualitatively the first excited states of Na and Cs in liquid He. Earlier work in this direction was given in detail in Ref. [263]. [Pg.167]


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See also in sourсe #XX -- [ Pg.108 , Pg.146 ]




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