Ferromagnetism in Organic Systems

The above models are based on physical insights gained from analysis of typically two site problems under simplified assumptions. To provide a quantitative basis for these models, it becomes necessary to deal with larger and more realistic systems. In this context, VB method becomes an invaluable tool, being a spin adapted method. Exact solution of large model systems afforded by the VB method allows introducing parameters that make the models more realistic. 

We have studied McConnell s kinetic exchange mechanism by dealing with a one- 

Substituted cyclophanes are the simplest systems in which opposite pin densities are stacked at sites directly above each. The spin resonance of several cyclophanes have been studied to test the McConnell[120] idea. Introducing a dicarbene substitution at each of the phenyl rings leads to unpaired electrons in the molecule. Following McConnell, we should expect the carbene spins to be aligned parallel if the substi- 

Nonlinear Optical Materials Theory and Modeling, (American Chemical Society, Washington, D.C., 1994) 

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