TABLE 1. Interspin Distances and Exchange Interactions.

compd	S	r (Å)	|J/k| (K)
1a	2, 1a	5-6b	∼1a
1b	1	5-6c	∼1a
2a	1	5-6d	>150
2b	1	6.0e	∼150
3	1	8-9f	>0.1

^aDetermined by magnetic susceptibility (ref 15).

^bCalculated from the X-ray crystal structure (ref 15).

^cEstimated interspin distances calculated from the dipolar splitting, the X-ray crystal structure, and the relative intensity of the half-field transitions are 5.7, 5-6, and 5.7 Å, respectively (ref 15).

^dEstimated interspin distances calculated from the dipolar splittings and average of nitroxyl N-N and O-O distances in the crystal structure of 4a (ref 16) (which does not account for spin delocalization into the aromatic ring) are 5.8 and 4.8 Å, respectively.

^eThe interspin distance calculated from the dipolar splitting is 6.0 Å. For the two isomers the average of N-N and O-O distances in the structures calculated by DFT are 4.9 and 6.2 Å, respectively.

^fDetermined from dipolar splittings (ref 18), single-crystal EPR (ref 17), and the relative intensity of the half-field transitions (ref 19).