Calculation of g Tensor Components

Accurate simulation of radical g tensors has only recently become possible, courtesy of accurate solvent models, ZORA approximation to Dirac equation, and the arrival of an accurate treatment of spin-orbit coupling within the density functional theory. All these methods are implemented in the ADF 2007 package, which was used for the g tensor calculations reported in Table 10.2. 

As these results show, there is very good agreement between the theoretical and the experimental values of the isotropic g factors. Thus, the anisotropic components obtained from the quantum chemical calculations may also be considered as reliable. These components are needed in the following two mechanisms contributing to spin relaxation. 

The relaxation mechanism depending on orientational modulation of the Zeeman interaction is determined by the anisotropy of the radicals g tensors. In an axially symmetric approximation, this anisotropy is given by 

In Ref. 23, we have assumed that gn equals the value ge of the free electron, 

TABLE 10.2 Theoretical Components of Radical g Tensors and Derived Quantities 

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