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Symmetric effects

Figure 14.6 compares measured and calculated isotope fractionations for all 16 possible ozone isotopomers prepared from an enriched oxygen precursor. In this figure (160160160, 160160170, 160170160, 160160180, etc. are represented as 666, 667, 676, 677, 767, 668, 686, 678, 777, 688, 868, 778, 787, 788, 878, and 888). The calculations are those of Gao and Marcus described in sections below. They are in quantitative agreement with experiment. It is interesting that isotope fractionations observed in product ozone for the totally symmetric isotopomers, 8170 = 1000 ln(777/666) and 8lsO = 1000 ln(888/666), are negative they show the heavy isotope to be depleted. Moreover, these totally symmetric effects lie on the mass dependent fractionation line [ln(777/666)]/[ln(888/666)] 0.5. That... [Pg.448]

Using the separation of the effective Hamiltonian into the unperturbed part and the perturbation, the total ionic contribution to the geminal is calculated exactly (vari-ationally). Only the bond polarity needs to be estimated perturbatively in the linear response approximation, but now the correlated ground state of the symmetric effective bond Hamiltonian is taken for evaluating the response function. In this context, it is convenient to use a dimensionless bond asymmetry parameter ... [Pg.213]

For symmetric effective coupling topogolies with = J23, the general transfer function T 2 of Eq. (193) can be reduced to... [Pg.126]

The transition state of the assisted ionization of 2-norbomen-7-yl p-nitrobenz-oate (395a) has been explored by comparison with the 2-methyl and 2,3-dimethyl derivatives, (402) and (403), respectively326. If participation stemmed from one end of the double bond, then the rate effect of 2,3-dimethyl substitution should double that of a 2-methyl group (statistical effect). The cumulative effect which was actually observed is evidence for the symmetrical nature of the transition state. Caution must be exercized, however, in extrapolating the symmetrical effects in the transition state to postulate a symmetrical carbocation. [Pg.223]

It is also noteworthy that the acceleration of the reaction provided by each of the catalyst components when added to the other is about the same. This symmetrical effect of the catalyst components on the activity of the system suggests a 1 1 complex between the catalyst components as the active species. The lack... [Pg.395]

Experiments on noble metal clusters (Cun, AgN, Aun) indicate the existence of shell-effects, similar to those observed in alkali clusters. These are reflected in the mass spectrum [10] and in the variations of the ionization potential with N. The shell-closing numbers are the same as for alkali metals, that is N = 2,S,20,40, etc. Cu, Ag and Au atoms have an electronic configuration of the type nd °(n + l)s so the DFT jellium model explains the magic numbers if we assume that the s electrons (one per atom) move within the self-consistent, spherically symmetric, effective jellium potential. [Pg.127]

Assuming that the refraction has a symmetrical effect on the path of light and the geoid is curved spherically, orthometric height differences 6H can then be obtained from and by... [Pg.293]

Pseudoplastic fluids in randomly generated porous media generate effective permeability fields, where zones of constant values are oddly shaped (bottle necks, among others, that can be considered scale up, equivalent to geometrical features, result of our mesoscale experiments), totally abnormal behavior can also be obtained for a different set of parameters. There seems to be a critical value for porosity to keep symmetric effective permeability fields. Our results can be used as models for materials with several zones... [Pg.96]

The nonlinearity of the Flamiltonian causes other asymmetry effects beyond those of the spin. Thus, for example, consider a spherically symmetric effective potential such as that of atoms. Then, the eigenstates of the exact Flamiltonian are also the eigenstates of the angular momentum operator L. Assume that the HF solutions have this property. Then, the spin orbitals must be the eigenstates of the HF equation (Equation 13.87). Then, for open shells, one shall have densities and density matrices that are not spherically symmetric because... [Pg.271]

Most neurotoxicants cause bilateral, symmetrical effects. Which one of the following neurotoxicants is the exception to this general mie ... [Pg.403]

As can be observed, the effects of variations on wind speed are greater in near field and decrease on far field, being the effect anti-symmetric on near field and tending to a symmetric effect on far field this occurs because near the source term there is more turbulence due to the jet and therefore there are more eddies generated by this turbulence. The wind contributes to the eddies formation and consequently to the cloud dilution. In far field, there is less turbulence thus, the wind... [Pg.16]

Generally, one wishes to allow for complex frequencies a>k = Re(cut) — iy /2, or similarly. t = Re(jr ) — iy /2, as long as Yk < C (t>, which is useful in calculating decay processes from the relevant levels. In this case, one has a complex symmetric effective Hamiltonian (or an even more general one) which it may not always be possible to diagonalize by the similarity transformation in equation (57). However, one can always compute the exponential function by a suitable series expansion in equation (59), which converges for all A ... [Pg.1781]


See other pages where Symmetric effects is mentioned: [Pg.330]    [Pg.58]    [Pg.19]    [Pg.39]    [Pg.254]    [Pg.264]    [Pg.273]    [Pg.839]    [Pg.122]    [Pg.64]    [Pg.332]    [Pg.181]   


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Bilateral symmetrical effects

Inertial effects linear and symmetrical top molecules

Stark effect in diatomic, linear and symmetric rotor molecules

Symmetric effects external field

Symmetric properties effect

Symmetric properties phase effects

Symmetrized squares, electronic states and the Jahn-Teller effect

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