Editing Metallocene (section)

===Vibrational (infrared and Raman) spectroscopy of metallocenes===

[[Infrared spectroscopy|Infrared]] and [[Raman spectroscopy|Raman]] spectroscopies have proved to be important in the analysis of cyclic polyenyl metal sandwich species, with particular use in elucidating covalent or ionic M–ring bonds and distinguishing between central and coordinated rings. Some typical spectral bands and assignments of iron group metallocenes are shown in the following table:<ref name="Metallocenes"/>

{| class="wikitable"
|+ Spectral frequencies of [[group 8 element|group 8]] metallocenes
! !! [[Ferrocene]] (cm<sup>−1</sup>) !! [[Ruthenocene]] (cm<sup>−1</sup>) !! [[Osmocene]] (cm<sup>−1</sup>)
|-
| C–H stretch || 3085 || 3100 || 3095
|-
| C–C stretch || 1411 || 1413 || 1405
|-
| Ring deformation || 1108 || 1103 || 1096
|-
| C–H deformation || 1002 || 1002 || 995
|-
| C–H out-of-plane bend || 811 || 806 || 819
|-
| Ring tilt || 492 || 528 || 428
|-
| M–ring stretch || 478 || 446 || 353
|-
| M–ring bend || 170 || 185 || –
|}