Abstract
Four bands have been observed for cyclobutane and six for cyclobutane-d8 in the Raman spectrum of the gas between 90 and 200 cm−1. These are due to the highly anharmonic ring puckering mode. The symmetric double minimum potential function for the puckering in C4H8 is V(cm−1) = 6.932 × 105χ4 − 3.790 × 104χ2, where χ is one half the distance between the ring diagonals in angstroms. The barrier height is 518 ± 5 cm−1 (1481 ± 14 calmole). For C4D8, V(cm−1) = 6.753 × 105χ4 − 3.705 × 104χ2 and the barrier height is 508 ± 8 cm−1 (1452 ± 23 calmole). For both molecules the equilibrium dihedral angle is 35°. The puckering transitions for C4H8 have also been measured in the infrared from (a) sum and difference tones with another fundamental at 1453.9 cm−1, (b) from difference tones with 2878.7 cm−1, and (c) from sum tones with 2986.7 cm−1. Only a portion of these data are given here because a very recent paper by stone and MILLS [Mol. Phys. 18, 631 (1970)] reports the same measurements. Our data and assignments agree almost exactly with theirs, so we do not repeat them in full.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Spectrochimica Acta Part A: Molecular Spectroscopy
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
