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Total, implied operation

In order to evaluate integrals over spin variables let us note that Eq. (5) implies that the symmetric group total spin operators S2 and S2. Consequently, the eigenfunctions of these operators form bases for representations of [Pg.614]

The quantities that hold the complete information, the states vectors T and 0(f), can be derived from fhe sysfem operator S2. This, in turn, means that the entire sought informatioiyis also present in or, equivalently, in U(f). The total evolution operator U(f) itself is the major physical content of C(f). Hence, fhe stated quantum-mechanical postulate on completeness implies that everything one could possibly learn about any considered system is also contained in the autocorrelation function C(f). Despite the fact that the same full information is available from T, 0(f), S2,U(f), and C(f), fhe autocorrelation functions are more manageable in practice, since they are observables. As a scalar, the quantity C(f) has a functional form fhaf is defined by its... [Pg.253]

The last equality in Eq. (1.7) implies that rr, when operating on a ket that does not contain leaves that ket unchanged, and that r r, when acting on a ket in which is present, leaves that ket alone. When r r operates on a ket in which is not present, it gives zero. Thus r r tells whether orbital (f>r occurs in a ket. For that reason, it is often referred to as the occupation number operator = r r. It is also conventional to introduce the total number operator N as N = which when operating on any ket gives... [Pg.3]

In our discussions of state and orbital correlations we have noted that 1. orbitals with different symmetries do not mix, 2. only states with the same symmetry mix in configuration interaction, and 3. states of the same symmetry do not cross. Therefore, symmetry plays a major role. Symmetry matters because the Hamiltonian for a molecule is a totally symmetric operator. This means that when it operates on a wavefunction, the resulting wavefunction has the same symmetry. Hence, the result of the operation IHI F> has the same symmetry as F. Further, the Hamiltonian does mix electronic states of like symmetry, while states of different symmetry lead to "no mixing". In other words, integrals of the sort and < lL, Fi,> must equal zero when Fa and have different symmetries. This implies that the energy of interaction is zero, and that... [Pg.887]

Visionary companies subscribe to a totally different operational mindset, termed the Wisdom of And. Examples include Safety AND productivity an extremely tight culture AND an ability to change and adapt a visionary, futuristic focus AND great daily execution. This mentality does not seek a mere balance — balance implies a 50-50 or a mid-point perspective. [Pg.38]

We need several properties of the spin operators. The commutation rules (1.2.20) for the spin operators of one electron, imply similar rules for the total spin operators (cf. Appendix 2) ... [Pg.89]

A fundamental mathematical feature of chemical systems is that the relevant Hamiltonian (total energy) operator can be written in terms of one-electron ) and two-electron (Pop44) operators only. This implies that all relevant chemical information can he obtained from reduced density operators that condense and simplify the iV-electron... [Pg.132]

The total refrigerant charge required in a circuit will vary with different operating loads and ambients, and must be sufficient at all times so that only liquid enters the expansion valve. This implies... [Pg.79]

If we restrict ourselves to the case of a hermitian U(ia), the vanishing of this commutator implies that the /S-matrix element between any two states characterized by two different eigenvalues of the (hermitian) operator U(ia) must vanish. Thus, for example, positronium in a triplet 8 state cannot decay into two photons. (Note that since U(it) anticommutes with P, the total momentum of the states under consideration must vanish.) Equation (11-294) when written in the form... [Pg.682]

Some plants can be operated essentially without any people. However, for safety purposes there usually are two employees per shift. Then if some mishap should occur to one man, the other can obtain help. This implies that a plant can be over-automated. The operators can become bored if they do not have some tasks to perform. If these are make-work tasks, the operators will rapidly determine this, and either the tasks will be ignored or the reports will be falsified. To keep these men alert, and sufficiently knowledgeable and involved so that they can respond quickly and properly when an emergency arises, it may be best not to automate the plant totally. [Pg.162]

The concentrations of the four A1 species occurring in each layer of the soil profile are expressed as a percentage of the A1 content of the specific soil layer. While Alpstot increased with depth of the profile, the contribution of the operationally defined A1 species towards speciation however decreased with depth (Figure 3a-d). The maximum differentiation of Alpstotas A1, A1, A1, and A1 was 8.51% which was observed in the surface layer while the mean contribution was 5.43 1.60%. On the contrary, in 37-57 cm depth which had the most abundant Alpstot, the mean share of the A1 species (2.72 0.75%) was the lowest contribution to A1 in all the layers of the soil profile. This implied that pseudo total A1 in these depths are predominantly bound as silicates and hence are not available for speciation under the experimental conditions. [Pg.79]

In Eq. (8.18), we wrote the potential as a convolution of the total density and the operator 1 /r. Similarly, the integrals encountered in the evaluation of the peripheral electronic contributions to Eqs. (8.35) (8.37) are convolutions of the electron density p(r) and the pertinent operator. They can be evaluated with the Fourier convolution theorem (Prosser and Blanchard 1962), which implies that the convolution of /(r) and p(r) is the inverse transform of the product of their... [Pg.179]

Moreover, Pernety also explains the meaning of the broader action implied by Duchamp s covert operations, namely gaining metaphorical Access. According to Pernety, hermetic Access (ITngres) is a very specialized sign—alchemical, and certainly not Freudian—of penetration leading to total fusion ... [Pg.328]

Monitoring such operations implies specific measures and modelling tools which correctly handle gas mixing phenomena. When such conditions are obtained the total saving is estimated at 20 % of the cushion gas cost. [Pg.174]

Clearly any attempt to base FeK on such molecularly defined cores defeats the aims of pseudopotential theory. However, the approximate invariance of atomic cores to molecule formation implies that, of the total of Na electrons which could be associated with the centre A in an atomic calculation, nx are core electrons and n K will contribute to the molecular valence set. Thus we can define a one-centred Fock operator ... [Pg.105]

Low-symmetry LF operators are time-even one-electron operators that are non-totally symmetric in orbit space. They thus have quasi-spin K = 1, implying that the only allowed matrix elements are between 2P and 2D (Cf. Eq. 28). Interestingly in complexes with a trigonal or tetragonal symmetry axis a further selection rule based on the angular momentum theory of the shell is retained. Indeed in such complexes two -orbitals will remain degenerate. This indicates that the intra-t2g part of the LF hamiltonian has pseudo-cylindrical D h symmetry. As a result the 2S+1L terms are resolved into pseudo-cylindrical 2S+1 A levels (/l = 0,1,..., L ). It is convenient to orient the z axis of quantization along the principal axis of revolution. In this way each A level comprises the ML = A components of the L manifold. In a pseudo-cylindrical field only levels with equal A are allowed to interact, in accordance with the pseudo-cylindrical selection rule ... [Pg.51]

The first and the second law of thermodynamics allow the description of a reversible fuel cell, whereas in particular the second law of thermodynamics governs the reversibility of the transport processes. The fuel and the air are separated within the fuel cell as non-mixed gases consisting of the different components. The assumption of a reversible operating fuel cell presupposes that the chemical potentials of the fluids at the anode and the cathode are converted into electrical potentials at each specific gas composition. This implies that no diffusion occurs in the gaseous phases. The reactants deliver the total enthalpy J2 ni Hi to the fuel cell and the total enthalpy J2 ni Hj leaves the cell (Figure 2.1). [Pg.16]


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See also in sourсe #XX -- [ Pg.15 ]




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Implied operation

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