Lande g-factors

Mixing of LS-states by spin orbit coupling will be stronger with an increasing number of f-electrons. As a consequence, intermediate values of Lande g factor and reduced crystal field matrix elements must be used. 

The number of energy levels found to date, with the aid of the Zeeman effect and the isotope shift data, is 605 even and 586 odd levels for Pu I and 252 even and 746 odd for Pu II. The quantum number J has been determined for all these levels, the Lande g-factor for most of them, and the isotope shift for almost all of the Pu I levels and for half of those of Pu II. Over 31000 lines have been observed of which 52% have been classified as transitions between pairs of the above levels. These represent 23 distinct electron configurations. 

The unpaired d electrons in an isolated transition metal ion or atom possess orbital angular momentum in addition to the spin momentum, and these couple together to give a total angular momentum J. The Zeeman interaction for these ions can be expressed by Eqs. (1) and (2) if S is replaced by J and g by the Lande g factor ... 

Starting from a multipole expansion of intramolecular Coulomb interactions, we present an efficient configuration interaction calculation for the electron terms = 2,3, 4, and the hole terms (hf)", n = 2-5. We have studied magnetic moments for the electron and hole terms. The coupling of spin and orbital momenta differs from the Lande g-factor scheme of atoms. The magnetic moments do not depend on the orientation of the molecule with respect to an external magnetic field. 

Auzinsh, M.P., Tamanis, M.Ya. and Ferber, R.S. (1985). Simultaneous determination of the Lande g factor and relaxation rate of the ground state for diatomic molecules using the Hanle effect, Opt. Spectrosc. (USSR), 59, 828-829. 

Figure 2(a) shows the ESR signal measured for two temperatures and fits using an assymetric Dysonian line shape. The fit allows us to determine the Lande g factor and the line width (AH) gives us a measurement of the spin scattering time ts using (f//// A//)rs = h. 

In the case of cubic symmetry (Fig. la), the px, p 1, and p2 orbitals of the 0 ions would be degenerate, so one is dealing with a 2P state. For zero magnetic field, the 2P state will be split by spin-orbit coupling into two states in which the orbital (L) and spin (S) angular momenta couple (Fig. 2). For small magnetic fields (flH 2, which would apply to normal EPR, since A 135 cm"1), the g value in each level is given by the Lande g factor... 

In the case of LS or Russell39-Saunders40 coupling (J is a good quantum number), and neglecting small corrections due to quantum electrodynamics, the Lande g-factor is given by... 

The factor g in Eqs. 8.14 and 8.15 is a dimensionless quantity called the electron, or Lande g factor (or spectroscopic sphtting factor) and, for the case of a. free electron, it equals precisely 2.0023193. However, it will be seen later that it can have other values when the electron is in condensed matter. 

In the case of spin-only paramagnetism, the Lande g factor is 2, since L = 0. The Curie law... 

The parameter g, the Lande g factor, has a value close to 2 for electrons in free space and in practice for most organic radicals. 

The constant of proportionality g equals 2.0023 for a free electron and is called the spectroscopic splitting factor, or just the g factor. It is equivalent to the Lande g factor of atomic spectroscopy. 

Lande g-factor B - Field strength fj,g- Bohr magneton... 

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