Electron exchange magnetic

To understand the sample (material) magnetism, one needs to comprehend the nature of molecular magnetism. The two paramagnetic components of the salt can take part in electron exchanges (EE). One type of electron exchange is D+ <— A and the other is D+ — A . These types of electron interactions are depicted in EE graphs from 1 to 5 in Scheme 8.14. 

Magnetic nuclei associated with orbitals in the 7r-electron system can also exhibit HFS. The interactions that describe the HFSC of such nuclei involve electron exchange between adjacent atoms as well as between the unpaired electron and the core electrons of the particular atom. These expressions are complicated and are derived on theoretical grounds in References 10 and 11, and empirical parameters for many heteroatoms are tabulated in References 1, 6, and 11. 

The number of electrons exchanged on a time scale similar to that of a preparative electrolysis is determined by coulometry. A coulometry experiment involves the complete conversion of the substrate to product(s) and, accordingly, C 0 decreases with time, in principle to zero. This is in contrast to the electro analytical methods where C 0 stays essentially constant during the experiments. Coulometry is carried out at either constant potential or constant current and, usually, the solution is stirred magnetically. 

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