Ligands, paramagnetic

This confirms the exceptional efficiency of these radicals in transmitting the magnetic interaction, already evidenced in the case of Gd-radical chains. The strategy based on paramagnetic ligands seems therefore to be the most suited for obtaining 4f based SCM. 

The neutral radical 84 is an interesting heterocyclic analogue of 2,2 -bipyridyl. This paramagnetic ligand forms an A A -chelated complex with b (hexafluoroacetylacetonato)cobalt(lI).221... 

The kinetics and stoicheiometry of the oxidation of oxovanadium(iv) by peroxide have been studied and continuous-flow e.s.r. techniques used to investigate the intermediate which appears to be a vanadium(v) complex with a paramagnetic ligand, formulated as either [OVOO,aq] or [V02(H02). aq]. Six- and seven-co-ordinate vanadium(v) has been identified by. Y-ray crystallography in the peroxo-complexes (NH4)[V0(02)2-Nh ]36o (NH4)4[0 V0(02)2 2] respcctively. and seven-co-ordination... 

Electron paramagnetic Ligand-protein interactions rhGH, rhlFN-y [54]... 

Numerous transient paramagnetic compounds are known and some of these are also shown in Table IV there is an overlap with Section V, and Table IV does not duplicate material which is more conveniently treated later. The distinction is arbitrary, but we shall defer consideration of transient transition metal-centered radicals, e.g., Pt(I), if their formation is primarily of interest in connection with an organometallic mechanistic study, e.g., the oxidative addition of an alkyl halide to a Pt(0) substrate. The designation of metal oxidation state in Table IV is somewhat formal in many cases it might be more appropriate to describe a complex as derived from a paramagnetic ligand, such as a nitroxide or ketyl. 

Medzhidov, A.A., Likhtenshtein, G I. and Kirichenko, L.A. (1969) Metallocomplexes with the paramagnetic ligands. Bulletin of the Academy of Science of USSR (Chemistry) N 3, 698-902. 

In the following part of this Section, we will report calculations on some systems which model super-exchange in transition metal dimers and direct exchange in transition metal complexes with paramagnetic ligands (Section 3.1), and the double exchange in mixed valence sterns (Section 3.2). 

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