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Phase factor difference

With Acp = (pltM — phase contribution can be rewritten as... [Pg.109]

Note, that this phase factor differs by (—l)2 from the phase factor that defines the standard phase system (Eq. (4) in the Introduction). This difference manifests itself only at half-integer values of momentum j. This change in the definition of the standard phase system is caused by the presence of commonly accepted phase relations in the second-quantization method [12, 96]. [Pg.119]

Let us now look at Ha/j(k), from Eq. (3-22), where a corresponds to a cations orbital and j8 to an anion s orbital. Each orbital matrix elements between it and the four neighboring orbitals s">, indicated in Fig. 3-7 each of these neighboring orbitals enters the matrix element with a phase factor differing from that of the (s > orbital by... [Pg.75]

An alternative perspective is as follows. A 5-frmction pulse in time has an infinitely broad frequency range. Thus, the pulse promotes transitions to all the excited-state vibrational eigenstates having good overlap (Franck-Condon factors) with the initial vibrational state. The pulse, by virtue of its coherence, in fact prepares a coherent superposition of all these excited-state vibrational eigenstates. From the earlier sections, we know that each of these eigenstates evolves with a different time-dependent phase factor, leading to coherent spatial translation of the wavepacket. [Pg.238]

Defining EJh + oij, replacing v /(-co) by v r(0), since the difference is only a phase factor, which exactly cancels in the bra and ket, and assuming that the electric field vector is time independent, we find... [Pg.244]

The quantum phase factor is the exponential of an imaginary quantity (i times the phase), which multiplies into a wave function. Historically, a natural extension of this was proposed in the fonn of a gauge transformation, which both multiplies into and admixes different components of a multicomponent wave function [103]. The resulting gauge theories have become an essential tool of quantum field theories and provide (as already noted in the discussion of the YM field) the modem rationale of basic forces between elementary particles [67-70]. It has already been noted that gauge theories have also made notable impact on molecular properties, especially under conditions that the electronic... [Pg.100]

We also describe a tracing method to obtain the phases after a full cycling. We shall further consider wave functions whose phases at the completion of cycling differ by integer multiples of 2jc (a situation that will be written, for brevity, as 2Nn ). Some time ago, these wave functions were shown to be completely equivalent, since only the phase factor (viz., is observable... [Pg.130]

The first and second terras contain phase factors identical to those previously met in Eq. (82). The last term has the new phase factor [Though the power of q in the second term is different from that in Eq. (82), this term enters with a physics-based coefficient that is independent of k in Eq. (82), and can be taken for the present illustration as zero. The full expression is shown in Eq. (86) and the implications of higher powers of q are discussed thereafter.] Then a new off-diagonal matrix element enlarged with the third temi only, multiplied by a (new) coefficient X, is... [Pg.141]

Other factors also impact the type of crystals formed upon cooling of hot soap. Water activity or moisture content contribute to the final crystal state as a result of the different phases containing different levels of hydration. Any additive that changes the water activity changes the crystallization pathway. For example, the addition of salt reduces the water activity of the mixture and pushes the equiUbrium state toward the lower moisture crystal stmcture. Additionally, the replacement of sodium with other counter cations influences the crystallization. For example, the replacement of sodium with potassium drives toward the formation of 5-phase. [Pg.152]

The parameters which characterize the thermodynamic equilibrium of the gel, viz. the swelling degree, swelling pressure, as well as other characteristics of the gel like the elastic modulus, can be substantially changed due to changes in external conditions, i.e., temperature, composition of the solution, pressure and some other factors. The changes in the state of the gel which are visually observed as volume changes can be both continuous and discontinuous [96], In principle, the latter is a transition between the phases of different concentration of the network polymer one of which corresponds to the swollen gel and the other to the collapsed one. [Pg.111]

Values of the general d function in the x, y, and z directions are shown in Figure 1 as a function of a. The functions in each region differ from those in the other two regions by at most a phase factor, —1, and a rotation, which serves to permute the variables x, y, and z. [Pg.239]

The wave vectors k can be expressed in terms of any basis vectors we choose. At the moment there is neither a direct nor a reciprocal lattice. Using (II.3a) in (II. 1) we see that the Fourier components of two indistinguishable densities can differ only by a phase factor ... [Pg.129]

If g is an element of the point group of the material meaning that p(r) and p(gr) are indistinguishable for all elements g in that group, corresponding Fourier components can differ only by a phase factor ... [Pg.129]

Thus the point group part of the operation works on the momentum coordinates and the translation part gives rise to a phase factor. We notice that this phase factor reduces to 1 in the diagonal elements, or in general when the difference between the the two arguments of N(p,p ) is a reciprocal lattice vector. [Pg.131]

Phase densities differ by a Phase densities differ by only about 10%. factor of 100-10,000 1. Viscosity in both phases is Liquid phase viscosity moderate, solid low. phase rigid. Phase separation is rapid Phase separation is slow surface-tension and complete. effects prevent completion. Countercurrent contacting is Countercurrent contacting is slow and quick and efficient. imperfect. ... [Pg.3]

For a number of 1907 acentric reflexions up to 0.463 A resolution, the mean and rms phase angle differences between the noise-free structure factors for the full multipolar model density and the structure factors for the spherical-atom structure (in parentheses we give the figures for 509 acentric reflexions up to 0.700A resolution only) were (Acp) = 1.012(2.152)°, rms(A( >) = 2.986(5.432)° while... [Pg.29]


See other pages where Phase factor difference is mentioned: [Pg.117]    [Pg.87]    [Pg.117]    [Pg.87]    [Pg.239]    [Pg.4]    [Pg.13]    [Pg.43]    [Pg.44]    [Pg.53]    [Pg.63]    [Pg.80]    [Pg.81]    [Pg.98]    [Pg.141]    [Pg.143]    [Pg.149]    [Pg.1989]    [Pg.41]    [Pg.41]    [Pg.731]    [Pg.19]    [Pg.141]    [Pg.701]    [Pg.24]    [Pg.125]    [Pg.153]    [Pg.244]    [Pg.324]    [Pg.108]    [Pg.117]    [Pg.147]    [Pg.148]    [Pg.157]    [Pg.167]   
See also in sourсe #XX -- [ Pg.109 ]

See also in sourсe #XX -- [ Pg.12 ]




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