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Electron multi

Eden, R. C., Application of Synthetic Diamond Substrate for Thermal Management of High Performance Electronic Multi-Chip Modules, in Applications of Diamond Films and Related Materials, (Y. Tzeng, etal., eds.), Elsevier Science Publishers, pp. 259-266(1991)... [Pg.382]

Nevertheless, the one-electron approach does have its deHciencies, and we believe that a major theoretical effort must now be devoted to improving on it. This is not only in order to obtain better quantitative results but, perhaps more importantly, to develop a framework which can encompass all types of charge-transfer processes, including Auger and quasi-resonant ones. To do so is likely to require the use of many-electron multi-configurational wavefunctions. There have been some attempts along these lines and we have indicated, in detail, how such a theory might be developed. The few many-electron calculations which have been made do differ qualitatively from the one-electron results for the same systems and, clearly, further calculations on other systems are required. [Pg.366]

Since the exact solution of Schrodinger s equation for multi-electron, multi-nucleus systems turned out to be impossible, efforts have been directed towards the determination of approximate solutions. Most modern approaches rely on the implementation of the Born-Oppenheimer (BO) approximation, which is based on the large difference in the masses of the electrons and the nuclei. Under the BO approximation, the total wave-function can be expressed as the product of the electronic il/) and nuclear (tj) wavefunctions, leading to the following electronic and nuclear Schrodinger s equations ... [Pg.105]

Fig. 16.17. Mechanism of the carbocupration of acetylene (R = H) or terminal alkynes (R H) with a saturated Gilman cuprate. The unsaturated Gilman cuprate I is obtained via the cuprolithiation product E and the resulting carbolithiation product F in several steps—and stereoselectively. Iodolysis of I leads to the formation of the iodoalkenes J with complete retention of configuration. Note The last step but one in this figure does not only afford I, but again the initial Gilman cuprate A B, too. The latter reenters the reaction chain "at the top" so that in the end the entire saturated (and more reactive) initial cuprate is incorporated into the unsaturated (and less reactive) cuprate (I). - Caution The organometallic compounds depicted here contain two-electron, multi-center bonds. Other than in "normal" cases, i.e., those with two-electron, two-center bonds, the lines cannot be automatically equated with the number of electron pairs. This is why only three electron shift arrows can be used to illustrate the reaction process. The fourth red arrow—in boldface— is not an electron shift arrow, but only indicates the site where the lithium atom binds next. Fig. 16.17. Mechanism of the carbocupration of acetylene (R = H) or terminal alkynes (R H) with a saturated Gilman cuprate. The unsaturated Gilman cuprate I is obtained via the cuprolithiation product E and the resulting carbolithiation product F in several steps—and stereoselectively. Iodolysis of I leads to the formation of the iodoalkenes J with complete retention of configuration. Note The last step but one in this figure does not only afford I, but again the initial Gilman cuprate A B, too. The latter reenters the reaction chain "at the top" so that in the end the entire saturated (and more reactive) initial cuprate is incorporated into the unsaturated (and less reactive) cuprate (I). - Caution The organometallic compounds depicted here contain two-electron, multi-center bonds. Other than in "normal" cases, i.e., those with two-electron, two-center bonds, the lines cannot be automatically equated with the number of electron pairs. This is why only three electron shift arrows can be used to illustrate the reaction process. The fourth red arrow—in boldface— is not an electron shift arrow, but only indicates the site where the lithium atom binds next.
Again, the electron number is only for the electrons involved in the rate-determining step. For a multi-electron, multi-step reaction, na does not equal the total number of electrons involved in the whole reaction. For example, in the ORR, the total number of electrons is four however, the apparent electron number... [Pg.20]

Liquid chroma- Atmospheric pres- Chemical ionisation Time-of-flight Electron multi- Photographic... [Pg.27]

In the most recent version of the energy-consistent pseudopotential approach the reference data is derived from finite-dilference all-electron multi-configuration Dirac-Hartree-Fock calculations based on the Dirac-Coulomb or Dirac-Coulomb-Breit Hamiltonian. As an example the first parametrization of such a potential,... [Pg.825]

Note that the one-electron Hamiltonian effective matrix components differ from those of Eq. (43) in what they truly represent. In this form, it represents the kinetic energy plus the interaction of a single electron with the core electrons around all nuclei present. The other integrals appearing in Eq. (52) are generally called two-electron-multi-centers integrals and are written as ... [Pg.197]

Menzinger M. 1988. The M -E X2 reactions paradigms of selectivity and specificity in electronic multi-channel reactions . In Selectivity in Chemical Reactions, Whitehead JC (ed.). Kluwer Academic Dordrecht 457-479. [Pg.475]

Excitation energies (eV) of Ce for the average of a nonrelativistic configuration from finite difference calculations with various ab initio pseudopotentials in comparison with all-electron multi-configuration Dirac-... [Pg.655]

THE M + X2 REACTIONS PARADIGMS OF SELECTIVITY AND SPECmCITY IN ELECTRONIC MULTI-CHANNEL REACTIONS... [Pg.457]

In fact, by considering the molecules, the treated systems become not only multi-electronic, but also multi-nuclei, so that must be studied the electronic state in the common field of nuclei. The case of file periodic field of nuclei will correspond to the metallic state and bonding. These sections, detail the quantum image of the multi-electronic multi-nuclei state. [Pg.143]

Proton-coupled electron transfer (PCET) is a ubiquitous process in biology and chemistry and plays an essential role in multi-electron, multi-proton transfer processes of biological relevance, such as photosynthesis and respira-tion. The coupling between proton and electron motions stabilizes reaction intermediates, by preventing charge build-up during the accumulation of redox equivalents. The key role of PCET natural photosynthesis is probably the major contributor to this effect. [Pg.127]


See other pages where Electron multi is mentioned: [Pg.338]    [Pg.99]    [Pg.144]    [Pg.436]    [Pg.113]    [Pg.63]    [Pg.179]    [Pg.825]    [Pg.826]    [Pg.834]    [Pg.255]    [Pg.169]    [Pg.428]    [Pg.164]    [Pg.127]    [Pg.137]    [Pg.158]    [Pg.436]    [Pg.19]    [Pg.361]   
See also in sourсe #XX -- [ Pg.275 ]




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Angular momentum in multi-electron species

Carbon dioxide multi-electron reduction

Coherent multi-electron transfer

Describing electrons in multi-electron systems

Discrete Variational Multi Electron

Electron coherent multi

Excited states multi-electron processes

Fabrication of Multi-Layer Silicone-Based Integrated Active Soft Electronics

Low-dimensional multi-electron

Multi-Electron Atoms in the Mendeleev Periodic Table

Multi-Electronic Orbitals in the Crystal Field

Multi-center electron transfer

Multi-configuration self-consistent field electron correlation methods

Multi-configurational self-consistent fields electronic structure

Multi-determinant wave functions electron correlation methods

Multi-electron Photoprocesses

Multi-electron Schrodinger equation approximation

Multi-electron atoms

Multi-electron atoms orbital energy

Multi-electron calculations

Multi-electron charge-transfer reactions

Multi-electron electrochemical reaction

Multi-electron mechanisms

Multi-electron mechanisms of redox reactions Switching molecular devices

Multi-electron processes

Multi-electron reaction

Multi-electron redox reactions

Multi-electron states

Multi-electron systems

Multi-electron transfer

Multi-electron transfer process

Multi-electron transfer reaction

Multi-electron wavefunction

Multi-reference coupled electron-pair

Multi-step electron-transfer process

Multi-vibrational electron transitions

Orbital quantum number multi-electron species

Scattering by a multi-electron atom

Single versus Multi-Electron Processes

Single- and Multi-electron Transfer Processes

Spin quantum number multi-electron species

Variational theory multi-electron atoms

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