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Matrix elements contributions

If Lhc live iiul c pun lien i oiic-ceiiicr iwo-cIccLroii integrals are expressed by symbols such as Gss, Gsp, defiiietJ above, then the Fock matrix element contributions from the one-center two-elec-iron in icgrals are ... [Pg.291]

The corresponding level broadening equals half. In fact is the diagonal kinetic coefficient characterizing the rate of phonon-assisted escape from the ground state [Ambegaokar 1987]. In harmonic approximation for the well the only nonzero matrix element is that with /= 1,K0 Q /> = <5o, where is the zero-point spread of the harmonic oscillator. For an anharmonic potential, other matrix elements contribute to (2.52). [Pg.26]

In order to determine the relations among orbital exponents in a basis which will follow these guidelines, we look at the matrix elements contributing to on(q). To that end we consider eq. 17 for the plane wave operator (eq. 21) which involves evaluation of terms of the sort (p e i /i). We wish to determine how these matrix elements behave as a function of orbital exponent and momentum transfer, and we then propose a scheme for choice of orbital exponents that will keep the BSR satisfied to as high momentum transfer as possible. [Pg.182]

These matrix elements contribute with one sign for the positive parity matrix and with the opposite sign for the negative parity matrix. Note that, because itu) commutes with the laboratory-fixed inversion operator E, which defines parity, matrix elements between states of opposite parity are rigorously zero. [Pg.619]

Note that the matrix element Amn is a constant that is independent of the particular state of the molecule, and the products of the ck describe the extent to which each matrix element contributes to state i. [Pg.281]

Equn. (4.119) for the partial-wave potential matrix element shows why only a finite number of partial-wave T-matrix elements contribute to the scattering. For very large L the centrifugal barrier means that UL kr) is appreciably greater than zero only for values of r greater than r , beyond which V(r) is effectively zero. Note also that there is a range of L for which (fc IIFLllfc") is so small that the Born approximation is valid... [Pg.103]

The complete set of interaction sequences incorporated in the fourth-order term for Mfi are accounted for by 96 time-ordei ed diagrams, in the general case, 48 of which are associated with the cooperative mechanism and 48 with the distributive mechanism examples of each type are shown in Fig. 8. The matrix element contribution for the cooperative mechanism corresponding to Fig. 8(a), for example, when evaluated using Eq. (5.7) gives the following result ... [Pg.55]

Working in a similar way, it is found that there are 24 contributions arising from diagrams of the distributive type represented in Fig. 8(b), where both real photons are absorbed at center A, and a virtual photon conveys the energy mismatch to B the final 24 distributive contributions arises from the mirror-image case where both real photons are absorbed at B and the virtual photon propagates to A. The addition of all 96 matrix element contributions then produces the complete fourth-order result for M -j. [Pg.56]

It turned out [201] that a special s)mimetrized form of the Breit operator leads to more simplified matrix elements contributing to the electronic energy expression. The total Breit operator in its cu-dependent form and also in the long-wavelength limit is symmetric with respect to an interchange of the electron coordinates 1 and 2. For Bq (1, 2) this symmetry holds even for the radial and angular coordinates independently. However, this is not the case for the... [Pg.339]

These imply that the electronic matrix element contributes... [Pg.183]


See other pages where Matrix elements contributions is mentioned: [Pg.379]    [Pg.35]    [Pg.198]    [Pg.198]    [Pg.148]    [Pg.754]    [Pg.366]    [Pg.232]    [Pg.333]    [Pg.316]    [Pg.87]    [Pg.104]    [Pg.275]    [Pg.254]    [Pg.327]    [Pg.328]   
See also in sourсe #XX -- [ Pg.171 ]




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