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The nuclear magnetic moment of the 158-kev, f~ state has been measured by precessing, in a solid gold environment, the f~(334 kev) |~ (158 kev)J~ gamma ray-gamma ray angular correlation in an external magnetic field of 26 000 gauss. The value obtained,juf = -j-l.03rk0.08 nm, includes a 5% correction for quadrupole attenuation as determined by studying the angular correlation as a function of the delay of the intermediate state. The value is compared to the recent prediction of de-Shalit assuming that the f~ state originates from the coupling of the §~ ground state (ji p =* +0.504 nm) with the 2+ excitation of the core. The magnetic moment of the core excitation was obtained from the Ml gamma-ray mean life of the 50-kev transition between the |~(208 kev) and f~(158 kev) core-particle doublet. That mean life, determined to be r 7 (50) = (4.46±1.0)XlO~9 sec, leads to predicted magnetic moments of At CO re= (+0.33_o.25 +0,n ) mn and W=(-M).84_o.26 +0 -17 )nm.

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The synthesis and full characterization of a series of neutral ligand α-diimine complexes of aluminum are reported. The compounds [Al(L)Cl)][AlCl] [L = N, N'-bis(4-R-CH)-2,3-dimethyl-1,4-diazabutadiene] are structurally analogous, as determined by multinuclear NMR spectroscopy and solid-state X-ray diffraction, across a range of electron-donating [R = Me (2), Bu (3), OMe (4), and NMe (5)] and electron-withdrawing [R = Cl (6), CF (7), and NO (8)] substituents in the aryl side arm of the ligand. UV-vis absorption spectroscopy and electrochemistry were used to access the optical and electrochemical properties, respectively, of the complexes. Both sets of properties are shown to be dependent on the R substituent. Density functional theory calculations performed on the [Al(L)Cl)][AlCl] complex (1) indicate primarily ligand-based frontier orbitals and were used to help support our discussion of both the spectral and electrochemical data. We also report the reaction of the L ligand with both AlBr and AlI and demonstrate a different reactivity profile for the heavier halide relative to the lighter members of the group.

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