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Theorem transition moment

Another important application of Theorem V is that (Corollary V.2) the dipole length and dipole velocity transition moments are equivalent when computed with state-independent effective operators obtained with norm-preserving mappings. According to definition A (see Table I), these computations evaluate o( p /8)o, and (a r )3)oWith... [Pg.494]

Table III summarizes Theorems V-VII and their corollaries along with similar results for the other state-independent effective operator definitions. Appendix E demonstrates the analogs of Theorems V-VII, except the conservation by definitions A" and A " of [H, C] for C a constant of the motion which commutes separately with and V. This last point is proven in paper II. The analogs of Corollaries V.l and V.2 are obtained similarly to, respectively. Corollaries V.l and V.2. Just as with Corollary V.2, none of the equivalences between the dipole length and dipole velocity transition moments for definitions A", A , or A , / = I-IV, produces a sum rule for transition moments (see Appendix D). Table III summarizes Theorems V-VII and their corollaries along with similar results for the other state-independent effective operator definitions. Appendix E demonstrates the analogs of Theorems V-VII, except the conservation by definitions A" and A " of [H, C] for C a constant of the motion which commutes separately with and V. This last point is proven in paper II. The analogs of Corollaries V.l and V.2 are obtained similarly to, respectively. Corollaries V.l and V.2. Just as with Corollary V.2, none of the equivalences between the dipole length and dipole velocity transition moments for definitions A", A , or A , / = I-IV, produces a sum rule for transition moments (see Appendix D).
The great orthogonality theorem maybe needed to determine the irreducible representations of the product in equation 14.3. If it contains Aj, then the integral may be nonzero and the transition between and caused by absorption or emission of electromagnetic radiation, is considered allowed. On the other hand, if the combination of irreducible representations in equation 14.3 does not contain Aj, then the integral defined in the transition moment must be identically zero and the transition cannot occur. It is a forbidden transition. [Pg.476]

The one-to-one correspondence of alloy and host sites is seen explicitly in Eq. (4). For the moment we now concentrate on the transition probability This quantity is proportional to the density of impurities and, according to the optical theorem, is given by... [Pg.469]

We shall encounter many examples of magnetic dipole spectra elsewhere in this book but note briefly here a few examples which again illustrate the importance of the Wigner-Eckart theorem in determining the selection rules. Rotational transitions in the metastable 1 Ag state of O2 provide an important example for an open shell system which does not possess an electric dipole moment [75]. The 1 Ag state arises from the presence of the two highest energy electrons in degenerate n-molecular orbitals if these orbitals are denoted 7r+1 and n j the wave functions for the 1 Ag state may be written... [Pg.271]

S-2S spectral transition of hydrogen. The same transition for antihydrogen holds the potential to put both CPT and the equivalence principle to the hest available test. A direct consequence of the CPT theorem is that particles and their antiparticles have identical masses, identical charges, and identical magnetic moments. It therefore follows that the spectra of hydrogen and anti-... [Pg.229]

The spectrum of the fluorescence field emitted on the 1) —> 2) and 13) —> 12) transitions is given by the Fourier transform of the average two-time correlation function of the dipole moments of the transitions that, according to the quantum regression theorem [33], satisfy the same equations of motion as the density matrix elements pj2( ) and P32W- Using the master equation (64) with the Hamiltonian (82), we obtain the following set of coupled equations of motion for the density matrix elements... [Pg.106]

Expansion of the function Bj in a Fourier series in q R-,) and applications of the Bloch theorem to the sum over i in eq. (7.24) leads to peaks in x whenever qm is a sub-multiple of a c-axis reciprocal lattice vector. The same argument can be made in the case of a spiral structure. The reasons for the incommensurate-to-commensurate q transition are to be found in (a) the single-ion anisotropy terms in the hamiltonian, including magnetoelastic effects. For CAM-type structures the axial anisotropy favors maximum ordered moment at each site which can only develop in a commensurate structure. For spiral-type structures the basal plane anisotropy will also favor a commensurate structure, as will the nagnetoelastic anisotropy (b) the exchange will also favor a maximum ordered... [Pg.504]

For exact wave functions and those that fulfill the hyper-virial theorem by construction [e.g., time-dependent Hartree-Fock (TDFIF) or random phase approximation (RPA), TDDFT, see below] both forms are equivalent. Note that all virial theorems are exactly fulfilled only in a complete (i.e., usually infinitely large) AO basis. By a simultaneous computation of the transition dipole moments in the length and velocity forms and subsequent numerical... [Pg.167]

RQMC (Sect. 18.2.3) was utilized in a study of transition metal oxides (ScO, TiO, VO, CrO, and MnO) their energetics and dipole moments [34,35]. Despite excellent agreement of the energetics with experiment, the dipole moments of these molecules significantly differed from experiment. After determining the errors associated with the pseudopotential approximation and the breakdown of the Hellmann-Feynman theorem to be small, the authors focused on the fixed-node error and the localization approximation employed in density functional theory. A multi-determinantal guiding function (better nodes) for TiO leads to an improved dipole moment, consistent with CCSD(T), but still somewhat larger than the value reported by experiment. [Pg.336]


See other pages where Theorem transition moment is mentioned: [Pg.149]    [Pg.336]    [Pg.75]    [Pg.169]    [Pg.525]    [Pg.75]    [Pg.376]    [Pg.193]    [Pg.306]    [Pg.324]    [Pg.167]    [Pg.193]    [Pg.164]    [Pg.330]    [Pg.3]    [Pg.420]    [Pg.281]    [Pg.438]    [Pg.285]    [Pg.31]    [Pg.43]    [Pg.190]    [Pg.55]    [Pg.664]    [Pg.261]    [Pg.330]    [Pg.1068]   
See also in sourсe #XX -- [ Pg.43 , Pg.216 ]




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