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Corrections state-independent

As an example of the connection between perturbation theory wave function corrections and polarizability, we now calculate the linear polarizability, ax. The states are corrected to first order in H. Since the polarization operator (Zx) is field independent, polarization terms linear in the electric field arise from products of the unperturbed states and their first-order corrections from the dipole operator. The corrected states are [12]... [Pg.98]

Continuing to the two-loop corrections, all terms known to date are state-independent, so we give only the ground state result [18,19,20],... [Pg.338]

Note that the properties of the reference state have canceled. This is to be e.xpected, since the solution to a change-of-state problem must be independent of the arbitrarily chosen reference state. This is an important point. In nature, the process will result in the same final state independent of our arbitrary choice of reference temperature, 7>. Therefore, if our analysis is correct. Tft must not appear in the final answer.)... [Pg.77]

Figure 21.18 displays a model for two independent sequential events where the first event occurs at rate a and the second rate occurs at rate p. Such a model can arise when a device with failure rate a is operated untQ it fads, whereupon it is replaced by a device with failure rate p. State S represents the first device operating correctly state A represents the first device having failed and the second device operating correctly and state B represents the second device having failed. [Pg.2275]

More informative deformation maps could be obtained by subtracting a correctly preoriented independent atom, or a reference atom in a corresponding state of hybridization. Features of one particular bond in a molecule can be most highlighted by subtracting the (calculated by MO methods) electron densities of the two fragments, differing from the molecule by the absence of only this bond. [Pg.948]

The weight of the correction is independent of the original state, depending only on the excitation process itself. [Pg.187]

VV e now wish to establish the general functional form of possible wavefunctions for the two electrons in this pseudo helium atom. We will do so by considering first the spatial part of the u a efunction. We will show how to derive functional forms for the wavefunction in which the i change of electrons is independent of the electron labels and does not affect the electron density. The simplest approach is to assume that each wavefunction for the helium atom is the product of the individual one-electron solutions. As we have just seen, this implies that the total energy is equal to the sum of the one-electron orbital energies, which is not correct as ii ignores electron-electron repulsion. Nevertheless, it is a useful illustrative model. The wavefunction of the lowest energy state then has each of the two electrons in a Is orbital ... [Pg.57]

In evaluating and/or designing compressors the main quantities that need to be calculated are the outlet (discharge) gas temperature, and the energy required to drive the motor or other prime mover. The latter is then corrected for the various efficiencies in the system. The differential equations for changes of state of any fluid in terms of the common independent variable are derived from the first two laws of thermodynamics ... [Pg.521]

Although the method is really independent of the correctness of the TST, it is convenient to consider the quasi-equilibria from the TST approach. They can be written for two situations, the reactant (R) and the transition state ( ),... [Pg.218]

Quantum mechanical effects—tunneling and interference, resonances, and electronic nonadiabaticity— play important roles in many chemical reactions. Rigorous quantum dynamics studies, that is, numerically accurate solutions of either the time-independent or time-dependent Schrodinger equations, provide the most correct and detailed description of a chemical reaction. While hmited to relatively small numbers of atoms by the standards of ordinary chemistry, numerically accurate quantum dynamics provides not only detailed insight into the nature of specific reactions, but benchmark results on which to base more approximate approaches, such as transition state theory and quasiclassical trajectories, which can be applied to larger systems. [Pg.2]

This most simple model for the relaxation time spectrum of materials near the liquid-solid transition is good for relating critical exponents (see Eq. 1-9), but it cannot be considered quantitatively correct. A detailed study of the evolution of the relaxation time spectrum from liquid to solid state is in progress [70], Preliminary results on vulcanizing polybutadienes indicate that the relaxation spectrum near the gel point is more complex than the simple spectrum presented in Eq. 3-6. In particular, the relation exponent n is not independent of the extent of reaction but decreases with increasing p. [Pg.194]

The OVGF function method provides a quantitative account of ionisation phenomena when the independent-particle picture of ionisation holds and as such is most applicable in the treatment of outer-valence orbitals. It provides an average absolute error for vertical ionisation energies below 20 eV of 0.25 eV for closed shell molecules. The TDA and ADC(3) methods allow for the breakdown of one particle picture of ionisation and so enable the calculation of the shake up spectra. The ADC(3) is correct up to 3rd order, is size consistent and includes correlation effects in both the initial and final states. [Pg.706]

The case is unusual and not quite correct, as no energy has been put into it since its initial creation, so that it is not in a true cyclic steady state. Friction, no matter how small, will cause the flow to stop it must produce some thermal entropy. Unlike a true cyclic system it is not truly time-independent and would require energy input to be so. We treat next a physical system where energy input is clear. [Pg.88]


See other pages where Corrections state-independent is mentioned: [Pg.57]    [Pg.183]    [Pg.236]    [Pg.341]    [Pg.341]    [Pg.184]    [Pg.441]    [Pg.53]    [Pg.1812]    [Pg.99]    [Pg.181]    [Pg.697]    [Pg.18]    [Pg.100]    [Pg.188]    [Pg.363]    [Pg.456]    [Pg.614]    [Pg.222]    [Pg.188]    [Pg.162]    [Pg.387]    [Pg.32]    [Pg.187]    [Pg.172]    [Pg.298]    [Pg.362]    [Pg.72]    [Pg.101]    [Pg.49]    [Pg.18]    [Pg.637]    [Pg.48]    [Pg.55]    [Pg.209]    [Pg.203]    [Pg.285]   
See also in sourсe #XX -- [ Pg.17 , Pg.183 , Pg.236 ]




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Corrected State

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