ELECTRONIC SPECTROSCOPY OF (CO)(5)W-AL[(R)DO(2)] COMPLEXES

Transition metal stabilized complexes of AL(I) with the formula (CO)(5 )W-Al[(R)(TMPDA)] (R = Cl (1), isobutyl (2); TMPDA = Me2N(CH2)(3)NMe2) show luminescence in the visible spectral region. The band maxima obs erved at 10 K are at 18 070 cm(-1) (553 nm) for 1, and at 17 630 cm(-1 ) (567 nn) for 2. Large Stokes shifts of 4150 and 4300 cm(-1) are dete rmined for 1 and 2, respectively. The low intensity of the first absor ption band and the long lifetimes of 130 mu s for 1 and 210 mu s for 2 (10 K) indicate a d-d transition. Luminescence spectra of microcrysta lline samples of 1 show a resolved progression with an average spacing of 530 +/- 10 cm(-1) (10 K) resulting from excited-state distortions along several different vibrational coordinates.