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Spin-orbit coupling, Jahn-Teller effect

Photoelectron spectroscopy Autoionization Koopmans approxlmaton Electron correlation Electron relaxation Closed shell systems Jahn-Teller effect Spin-orbit coupling Open shell systems Cross-sections, ligand Cross-sections, metal... [Pg.412]

II electronic states, 638-640 vibronic coupling, 628-631 triatomic molecules, 594-598 Hamiltonian equations, 612-615 pragmatic models, 620-621 Kramers doublets, geometric phase theory linear Jahn-Teller effect, 20-22 spin-orbit coupling, 20-22 Kramers-Kronig reciprocity, wave function analycity, 201 -205 Kramers theorem ... [Pg.83]

Spin multiplicity, permutational symmetry, dynamic Jahn-Teller and geometric phase effects, 706-711 Spin-orbit coupling conical intersections ... [Pg.98]

Liehr has shown (142) that the orbital degeneracy of the ground state in a tetrahedral nickel(II) complex may be lifted by spin-orbit coupling. This means that these complexes may not be liable to Jahn-Teller distortion as has been thought for some time. Such coupling would also have the effect of splitting all transitions into several components, the exact number... [Pg.155]

In connection with the Jahn-Teller effect the role of A may be well defined. It has been shown that if a dynamic Jahn-Teller effect is operative, very substantial quenching of orbital angular momentum may take place — the Ham effect. In the case of T ground terms, if the dynamic Jahn-Teller frequencies bear the right relationship to spin-orbit coupling and temperature, A may be reduced to values well below 0.5.113119... [Pg.265]

There remains the possibility of g-values which depart substantially from 2.00 but are isotropic because of cubic symmetry. In practice such conditions are rare for transition metal complexes, as the Jahn-Teller theorem ensures departure from cubic symmetry in the electronic structure. However, for the lanthanoid and actinoid elements, where the spin—orbit coupling constant is very much larger than kT, the Jahn—Teller theorem may not be relevant and effective cubic symmetry certain. For the lanthanoids, g-values often depart considerably from 2.00, although some anisotropy arising from ligand field splittings is common. For the actinoids, direct observation of ESR is less common but there is evidence of a similar situation. [Pg.270]

The C3V symmetry at the SI site imposes on the Cu ion term splitting (21) shown in Fig. 10. The relative separations A2 between the E-states and A3 between the lower E-state and the A-state depend on the angle between the Cu-0 bond and the threefold symmetry axis (22) and, conversely, from measured A2 and A3 one can determine 3. The E-states are split further by the Jahn-Teller effect and spin orbit coupling into E+ and E components, the energies of which are given by (21)... [Pg.165]

The increase of the Stokes shift in the sequence Te4+, Sb3+, Sn2+ is due to the first contribution. This is immediately clear by remembering that a strong spin-orbit coupling will quench the Jahn-Teller effect. Since Te4+ is the ion for which vibrational structure can just be observed, it is not surprising that the literature contains no examples of vibrational structure in the emission spectra of Sb3+ and Sn2+. [Pg.13]

In the 6s2 ions the contribution a will be weak due to the large spin-orbit coupling. If the contribution c is restricted due to a low coordination number and/or a small coordination polyhedron, only the contribution b remains. In fact, if the emission of 6s2 ions contains vibrational structure, it consists always of a progression in the alg vibrational mode. It is now also clear that this will be the easier observed if the charge is high, i.e. the spin-orbit coupling large, since this quenches the Jahn-Teller effect. [Pg.13]

All the off-diagonal matrix elements of the spin-orbit coupling in the >, Tl> [ basis are thus reduced by the factor y, and we use the experimentally observed quenching to calculate Ej j and the corresponding geometrical distortion (14). In the Cs2NaYClg host lattice the total spread of the four spin-orbit components of T2 is 32 cm whereas crystal field theory without considering a Jahn-Teller effect predicts a total spread of approximately 107 cm-. ... [Pg.9]


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See also in sourсe #XX -- [ Pg.375 ]




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Coupling 3/, orbital effects

Effective coupling

Jahn effect

Jahn-Teller

Jahn-Teller coupling

Jahn-Teller effect

Orbit coupling

Orbital effects

Spin effects

Spin-orbit coupling

Spin-orbit coupling effects

Spin-orbit effects

Spin-orbital coupling

Spin-orbital effect

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