RESONANCE RAMAN SPECTRA OF TRANSITION METAL DIMERS

Author Institution:Resonance Raman spectra of $Ti_{2}, V_{2}, Fe_{2}$ and FeNi isolated in argon matrices at 12 K have been observed. Spectra were generated with an argon ion laser or with an argon ion laser pumped dye laser equipped the Rhodamine 6G dye. The carriers of the observed progressions were identified from the isotopic fine structure of the bands, from comparison with known absorption spectra and from concentration studies. For $Fe_{2}, V_{2}$ and $Ti_{2}$ antistokes Raman were observed. The excited vibrational states giving rise to the antistokes bands must be populated by radiative decay processes in the matrix since they cannot be thermally populated. It was also observed that some of the stokes and antistokes Raman bands exhibit a more complicated fine structure than is expected. A mechanism is proposed which can be used to explain these observations