Vibrational Spectra ot cyclopentadienyl-renium-tricarbonyl

Vibrational Study of (η5-Cyclopentadienyl)metal Complexes

“…Of these, e 1 mode can be regarded as a ring tilt relative to the local C 5 axis and the e 2 mode has out-of-plane ring deformation character. The symmetric stretch a 1 (4′) for CpM(CO) 3 complexes is surely at 353 and at 327 cm -1 when M ) Mn 22,24,26 or Re, 23 straightforward for the other complexes. The other two bands, close to the strong totally symmetric ones, can be attributed to modes 11′ and 18′, the intermediate being probably e 1 , because of the essentially coincidence with a corresponding infrared absorption.…”

“…Of these, e 1 mode can be regarded as a ring tilt relative to the local C 5 axis and the e 2 mode has out-of-plane ring deformation character. The symmetric stretch a 1 (4‘) for CpM(CO) 3 complexes is surely at 353 and at 327 cm -1 when M = Mn 22,24,26 or Re, respectively. A similar assignment is straightforward for the other complexes.…”

“…The molecular symmetries are different and generally low, but the fragment CpM can be treated on the basis of the local C 5v symmetry. This assumption is usually accepted − and implies the exclusion of any coupling between the vibrations of the CpM fragment and of the L n fragment. This is clearly unacceptable as far as skeletal modes are concerned, but it may be valid for the intraring vibrations, which, as we have seen, are essentially uncoupled, even between two identical Cp rings.…”

Microwave measurements of rhenium quadrupole coupling in cyclopentadienyl rhenium tricarbonyl

“…[1][2][3][4][5] Several of these techniques [1][2][3][4] have indicated that the Cp group interacts with the C 3v symmetry, carbonyl portion of the molecule and exhibits a reduction in symmetry to C 2v . For these examples, the molecule would no longer be a symmetric top.…”