Physical Properties of Eleven-Atom Ligand Complexes

PHYSICAL PROPERTIES OF ELEVEN-ATOM LIGAND COMPLEXES 

The magnetic moments of several sandwich-bonded complexes with d electron configurations d5 through d9 are given in Table III. Most of the d5, Fe(III) complexes have a p,eff of about 2.3 /xB (Bohr magnetons). This is in good agreement with the experimental value /xeff = 2.34 fiB obtained 

The proton NMR spectra of the diamagnetic complexes have been useful in confirming parts of the structure of these compounds. The carborane CH resonance appears as a broad singlet in most proton spectra. The 11B NMR spectra of the diamagnetic complexes have to date been useless for structural purposes because of the complex overlap of the various doublets. 

The nB NMR spectra of paramagnetic species such as (1,2-B9H9C2H2)2 Fe (Fig. 9) exhibit unusually broad resonances containing no evidence of 

Reduction potentials for a variety of the 11-atom ligand complexes have been measured either by cyclic voltammetry or by polarographic methods (see Table IV). In certain cases the most stable formal oxidation state for 

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III. Physical Properties of Eleven-Atom Ligand Complexes. . . 104... 

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