Electron spin resonance study of adducts of gallium trichloride and digallium hexachloride with the free-radical base, 2,2,6,6-tetramethylpiperidine nitroxide
Abstract
Reaction of gallium trichloride with 2,2,6,6-tetramethylpiperidine nitroxide (TEMPO) yields two adducts, (I)(Ga2Cl6â†�TEMPO) with Aiso(14N)= 19·13 G, Aiso(71Ga)=–55·3 G and (II)(GaCl3â†�TEMPO) with g∥= 2·003, g⊥= 2·007, Aiso(14N)= 19·75 G, A∥(14N)= 39 G, A∥(71Ga)=–50 G, A⊥(71Ga)=–44 G, Aiso(71Ga)=–48·0 G. The principal values of the g-tensor are close to those for TEMPO alone, and the Ga hyperfine tensors show that the isotropic component stems from spin polarisation of the O–Ga σ electrons and the anisotropic component probably stems from polarisation of the O–Ga π-electrons.