Dinitroxide biradicals

Figure 6.1 Stick spectra for a dinitroxide biradical with a= 13 G for various values of the exchange coupling constant J. (Several very small, widely spaced resonances have been omitted for J=2A and J=5A.)...

A second class of molecules with two unpaired electrons has the two electrons localized, to a first approximation, in different parts of the molecule. We refer to such molecules as biradicals (or, with three or more unpaired electrons, triradicals, etc.). Examples are the dinitroxides (e.g. 1), and certain binuclear vanadium(iv) and copper(n) complexes. 

The dinitroxide (20) is one of several nitroxide biradicals used to test the point-dipole approximation for electron-electron dipolar interactions/ ... 

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