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Three coupling

Here, dj = cos(y,j) and sy = sin(Yy). The three angles are obtained by solving the following three coupled first-order differential equations, which follow from Eq. (19) [36,84,85] ... [Pg.659]

In Section V.B, we discussed to some extent the 3x3 adiabatic-to-diabatic transformation matrix A(= for a tri-state system. This matrix was expressed in terms of three (Euler-type) angles Y,y,r = 1,2,3 [see Eq. (81)], which fulfill a set of three coupled, first-order, differential equations [see Eq. (82)]. [Pg.729]

All three coupling procedures are suitable to give high yields under mild reaction conditions. Many functional groups do not interfere. For the application in organic synthesis the Eglinton variant may be more convenient than the Glaser method a drawback however is the need for stoichiometric amounts of copper salt. [Pg.137]

On the basis of all these results and his own investigations on chloro- and bromo-de-diazoniations (Galli, 1981), Galli proposed in 1988 that iodo-de-diazoniation, after formation of the aryl radical in the initiation reaction (Scheme 10-22) follows three coupled iodination chain reactions based on the formation of the I2 molecule and the If anion in the step shown in Scheme 10-23, namely iodine atom (I ) addition (Scheme 10-24), and iodine abstraction from I2 and If in Schemes 10-25 and 10-26 respectively. Aryl radicals and iodine molecules are regenerated as indicated in Scheme 10-27. The addition of iodide ion to aryl radicals forming the radical anion [Arl] -, as in Scheme 10-28, is considered an unlikely pathway, as that reaction has been found to be reversible (Lawless and Hawley, 1969 Andrieux et al. 1979). [Pg.236]

If we compare results obtained with the same basis sets with the three coupled cluster models CCS, CC2 and CCSD, we find similar trends as observed in Refs. [22,45] The CCS model underestimates strongly the static hyperpolarizabilities and their dispersion. The results are usually of similar quality as those obtained with SCF. For methane, the CCS static hyperpolarizabilities are intermediate between the SCF and the CCSD values obtained in the same basis set. In Ref. [45] the CCS percentage dispersion contribution to the third harmonic generation (THG) hyperpolarizability of methane was found to be slightly smaller than for SCF, both underestimating significantly the dispersion obtained with the correlated coupled cluster models CC2 and CCSD. Accordingly the CCS dispersion coeflBcients listed in Table 3 are substantially smaller than the respective CCSD results obtained in the same basis sets. [Pg.137]

The ideas in Section IVA have been extended to three coupled angular momenta by Grondin et al. [3], in the context of a Hamiltonian of the form... [Pg.70]

Coupling of the receptors is very similar with all three coupling to Gq and increasing IP3/DAG and in a number of neuronal systems it has been shown that the receptors produce slow depolarising responses via the closing of potassium channels. [Pg.260]

As before, the chiral centre renders Ha and Hb non-equivalent and for the reasons already covered, Hx will couple to both with all three couplings (Ha-Hb, Ha-Hx and Hb-Hx) likely to be different. So the classical presentation of an ABX system is that of three multiplets, each of four lines. (Note that in Spectrum 6.2, the size of the Ha-X and the Hb-X couplings are almost identical so the X proton appears as an approximate triplet. This is quite common.). The AB part indicates that the geminal pair are likely to be relatively close in terms of chemical shift, whilst the X proton is someway distant from both. Obviously, the scope for variation in the appearance of ABX systems is enormous. The difference in chemical shift between Ha and Hb is a major factor in this but we have also come across ABX systems... [Pg.69]

Navarro E, Bacardit M, Caputo L, Palau T, Armengol J (2006) Limnological characterization and flow patterns of a three-coupled reservoir system and their influence on Dreissena polymorpha populations and settlement during the stratification period. Lake Reservoir Manage 22 293-302... [Pg.94]

The selected electrodes (five n-type and four p-type) were used to obtain kinetic current vs. potential data in solutions containing poised ferrocene redox couples (50% oxidized, 50% reduced) (37.391. The electrode potential was varied over a range of at least 0.5 V to over 1.0 V. Three couples were examined ferrocene (FER) itself, decamethylferrocene (DFER) and acetylferrocene (AFER). The reduction potentials of DFER and AFER with respect to FER (which is assigned a value of 0.0) are -0.50 and +0.25 V, respectively. The reduction potentials for all three couples are located between the CBE and VBE of the WSe2-CH3CN interface. [Pg.443]

The symmetry-adapted operators of benzene with symmetry D6h are those corresponding to these three couplings, that is,... [Pg.138]

Wu, G. (1991), The Semiclassical Fixed Point Structure of Three Coupled Anharmonic Oscillators Under SU(3) Algebra with Iz = 0, Chem. Phys. Letts. 179, 29. [Pg.236]

The first part of the analysis was conducted to detect the designs with minimum energy consumption for the integrated sequences. Once a validated design (tray structure) was obtained, an optimization procedure was carried out on the recycle streams for each of the three coupled sequences to detect the operating conditions under which each design was more energy efficient. [Pg.61]

In an alternative formulation of the Redfield theory, one expresses the density operator by expansion in a suitable operator basis set and formulates the equation of motion directly in terms of the expectation values of the operators (18,20,50). Consider a system of two nuclear spins with the spin quantum number of 1/2,1, and N, interacting with each other through the scalar J-coupling and dipolar interaction. In an isotropic liquid, the former interaction gives rise to J-split doublets, while the dipolar interaction acts as a relaxation mechanism. For the discussion of such a system, the appropriate sixteen-dimensional basis set can for example consist of the unit operator, E, the operators corresponding to the Cartesian components of the two spins, Ix, ly, Iz, Nx, Ny, Nz and the products of the components of I and the components of N (49). These sixteen operators span the Liouville space for our two-spin system. If we concentrate on the longitudinal relaxation (the relaxation connected to the distribution of populations), the Redfield theory predicts the relaxation to follow a set of three coupled differential equations ... [Pg.54]

The term isotope was coined by Soddy (1914) to define two or more substances of different masses occupying the same position in the periodic chart of the elements. Soddy s hypothesis was adopted to explain apparent anomalies in the relative positions of three couples of elements (Ar-K, Co-Ni, and Te-I) in the periodic chart. For instance, potassium is present in nature with three isotopes with masses of 39, 40, and 41, respectively, in the following proportions = 93.26, = 0.01, and = 6.73. Because the pro-... [Pg.707]

Now we see that we appear to have three coupled first-order ordinary differential equations with Cc apparently coupled in the second and third equations. However, we can eliminate... [Pg.161]


See other pages where Three coupling is mentioned: [Pg.1454]    [Pg.3]    [Pg.25]    [Pg.283]    [Pg.468]    [Pg.315]    [Pg.44]    [Pg.474]    [Pg.31]    [Pg.130]    [Pg.23]    [Pg.39]    [Pg.70]    [Pg.265]    [Pg.58]    [Pg.357]    [Pg.134]    [Pg.252]    [Pg.407]    [Pg.500]    [Pg.216]    [Pg.192]    [Pg.119]    [Pg.169]    [Pg.209]    [Pg.304]    [Pg.781]    [Pg.783]   
See also in sourсe #XX -- [ Pg.184 ]

See also in sourсe #XX -- [ Pg.58 , Pg.556 ]




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Aldol three-component coupling

Alkynes three-component couplings

Allylic three-component coupling

Angular momentum three coupled momenta

Biginelli reaction three component coupling

Carbon coupling constants three-bond

Carbon-proton coupling constants three-bond couplings

Copper-catalyzed three-component coupling/intramolecular

Coupling constant, three-bond

Coupling constants three-bond couplings

Coupling constants, three-iron

Coupling of three angular momenta

Coupling over more than three bonds

Coupling over three bonds

Coupling reaction, three-component

Coupling, three component, “cation

Coupling, three component, “cation pool” method

Couplings over More than Three Bonds and Through Space

Electron Transfer Is Coupled to ATP Formation at Three Sites

Linchpin coupling, three-component

Mannich reaction three component coupling

Mannich-type three-component coupling

Multicomponent reactions three-component couplings

Ni-catalyzed three-component coupling reaction

Non-adiabatic coupling three-particle reactive system

Non-adiabatic coupling three-state matrix quantization

Non-adiabatic coupling three-state system analysis

Non-adiabatic coupling, Longuet-Higgins phase-based treatment, three-particle

Nucleophilic substitution three-component coupling reactions

One-pot three-component coupling

Potentials coupled three-dimensional problems

Prostaglandins three component coupling

Prostaglandins three-component coupling synthesis

Silver-catalyzed three-component coupling

Three Coupled Nuclei (AX2, AMX, ABX, ABC, AB2 Systems)

Three Coupled Reactors

Three component coupling reaction chiral phosphoric acid

Three-Bond (Vicinal) Coupling Constants

Three-Bond Coupling (3JCH)

Three-Bond Couplings CJ)

Three-Component Coupling Reactions via Aryl Carbanion Trapping by an External Electrophile

Three-bond (vicinal) coupling

Three-bond Couplings Between Hydrogen and Heteronuclei

Three-bond Couplings not Involving Hydrogen

Three-bond Couplings to Hydrogen

Three-bond coupling

Three-component coupling

Three-component coupling approach

Three-component coupling of silyltellurides, carbonyl compounds and isocyanides

Three-component coupling reaction, Strecker

Three-component coupling, reaction mechanism

Three-component coupling, strategy

Three-component couplings, alkyl group

Three-component couplings, alkyl group transfer

Three-component cyclo-coupling

Three-component tandem coupling reaction

Three-coupled angular momenta, quantum

Three-dimensional coupling

Three-fold cross-coupling

Three-state molecular system, non-adiabatic strongly coupled conical

Three-state system strongly coupled conical

Two- and three-bond coupling

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