Metallocene halides. Part II. The low frequency infrared and Raman spectra of di-π-cyclopentadienyldihalogeno-titanium(IV), -zirconium(IV), and -hafnium(IV)

Abstract

The low frequency i.r. and Raman spectra of the compounds (π-C₅H₅)₂MX₂(M = Ti, Zr, and Hf; X = F, Cl, Br, and I) have been studied in the solid state and in solution. The metal–halogen [for the chlorides and (π-C₅H₅)TiX₂(X = Br or I), there is uncertainty] stretching vibrations are assigned as follows [M, X, ν_sym(cm.^–1), ν_asym(cm.^–1)(i.r., soln.) Ti, F, 579, 550; Zr, F, 560, 545; Zr, Br, 223, 212; Zr, I, 190(?), 178; Hf, F, 562, 536; Hf, Br, 208 1 97; and Hf, I, 170, 153].