Knowledge Bank

The pseudorotation combination bands of cyclopentane near $1460cm-1$ have been reexamined at high resolution ($0.1cm-1$). Similar spectra have also been obtained for the $d1$ and $d10$ derivatives. The specings between adjacent combination bands are approximately 5.3, 5.0, and $3.9cm-1$ for the three compounds. Spectra for cyclopentane-$1,1-d2$ and $1,1,2,2,3,3-d6$ have also been examined. The effect on the spectra of a ten-fold pseudorotational barrier will be considered.