Interaction Between Magnetic Ions

Magnetic susceptibihty measurements [256] on Cu VCo VZn/Al LDHs indicate that the Cmie-Weiss law is obeyed with a Weiss temperature close to zero, indicating the lack of magnetic interactions between paramagnetic ions and thus a random distribution in the lattice. It has been proposed, however, that the catalytic activity of Mg Al LDHs n = 2,3) containing interlayer carbonate anions in the oxyethylation of 1-dodecanol with ethylene oxide can be correlated with the distance between AP" cations in ordered lattices [250]. 

Most of the data for this section came from Murad and Johnston (1987), Murad (1988) and Coey (1988). The main type of magnetic interaction between Fe ions on adjacent sites in a solid is the electrostatic exchange interaction this tends to cause... 

The magnetic interaction between lanthanide ions and coordinated ligands 1101... 

Finally, the magnetic interactions in the fee TMO (TM=Cu, Ni, Co, Fe, Mn) have been analyzed. We find the magnetic interaction decreases with decreasing nuclear charge on the TM ion. A comparison of magnetic interactions between bulk atoms and between atoms located at the (100) surface shows that the interaction in all five compounds is lowered at the surface. The calculated value of the interaction in bulk NiO compares rather well with the measured one, especially when charge transfer effects are included in a more complete manner by extending the active space in CASSCF. 

As was the case for RBso-type compounds and RB25 compounds, this is further experimental evidence that the B12 icosahedra are functioning as a novel mediator of the magnetic interaction between the rare earth ions. 

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