Vapour phase far-infrared studies of eta-bonded metal carbonyls, (1,3-butadieneiron tricarbonyl, cyclopentadienylmanganese tricarbonyl and methylcyclopentadienylmanganese tricarbonyl)

摘要

Far-infrared spectra of 1,3-butadieneiron tricarbonyl, C_4H_6Fe(CO)_3. cyclopentadienyl-manganese tricarbonyl, C_5HMn(CO)_3 and methylcyclopentadienylmanganese tricarbonyl. CH,C_5H_4Mn(CO)_3 in the vapour phase have been reported first time in the region 500- 10 cm~(-1). An assignment of the frequencies on the basis of local symmetry of Fe(CO)_3 fragment explain most of the observations, but the Fe-CO stretching modes of ￡ symmetry are split. The C_4H_6 vibrations are assigned on the basis of C_s symmetry. For CpMn(CO), and MeCpMn(CO)- particular reference is made to the assignment of the metal-ring modes. This assignment has been discussed in term of previous assignment given for (in liquid phase and Nujoll mull) other eta-cyclopentadienyl and related compounds, including ferrocene, dimethylferrocene, benzenechromium tricarbonyl and toluenechromium tricarbonyl.