Antiferromagnetic interaction between

The presence of /3-hydrogen in the nitroxide radical may lead to disproportionation reactions. In spin-trapping experiments, N-t-butyl-a-phenyl nitrone yields rather unstable spin adducts. This type of radical can be stabilized by coordination to Nin. The Ni11 complex with N-oxy-A-r-butyl-(2-pyridyl)phenylmethanamine (923) reveals a distorted octahedral geometry with antiferromagnetic interactions between the unpaired electrons of the metal ion and the radical spins.00... 

The Mn- Mn separations in both planar and butterfly complexes are very similar and range between 2.80 A and 3.45 A. The magnetic properties of these complexes have been studied extensively, and showed antiferromagnetic interactions between the manganese(III) centers. Electrochemical behavior of the butterfly conmlexes is summarized in Table 9 and both oxidative and reductive processes are observed. 

Other calculations of the Cr—Cr interaction are based on a model in which there is weak antiferromagnetic interaction between high-spin Cr2+ atoms.191 This is not believed to be realistic, at least for the supershort bonds. 7 A computational method which supposes multiple bonds to be single bonds intensified by screening of the internuclear repulsion is said not to support the antiferromagnetic interaction mode.1 ... 

Curie-Weiss behaviour from 309 to 83 K with a Weiss constant 6 s 10 K. The 3-carboxylate was studied in the range 275-4.2 K and the data were interpreted in terms of an antiferromagnetic interaction between silver ions using the Ising linear chain model. This gave an exchange energy of / = —30.8 1.0 cm-1 and g = 2.5 0.02 which was somewhat smaller than the experimentally determined (g) of 2.08.513... 

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