Raman spectra of ruthenium and tantalum trimers in argon matrices

The resonance Raman spectra of ruthenium trimers (Ru-3) in argon matrices h ave been obtained. Three resonance Raman transitions were observed between 570 and 590 nm. Two of them (303.4 and 603.7 cm(-1)) are assigned to the to tally symmetric vibrational progression, giving k(e) = 1.86 mdyne/Angstrom. The line at 581.5 cm(-1) is assigned as the origin of a low-lying electron ic state. We also report on the observation of a resonance Raman spectrum o f tantalum trimers (Ta-3). Observed lines include 251.2 and 501.9 cm(-1) wh ich we assign to the fundamental and the first overtone of the symmetric st retch in Ta-3. This gives k(e) = 2.25 mdyne/Angstrom. (C) 2000 Elsevier Sci ence B.V. All rights reserved.