Rotational spectrum, dipole moment, and ring-puckering potential of cyclobutane-1,1-d2

Conformational stability, r0 structural parameters, barriers to internal rotation and vibrational assignment of cyclobutylamine

“…This value is in good agreement with the r 0 value of 22.9(5)°obtained in this study for cyclobutylamine. A detail structural determination for chlorocyclobutane would be of interest for comparison to the structural parameters of cyclobutane which have been well determine [30] experimentally to be r(CAC) = 1.5549(5), r(CAH ax ) = 1.092 (2), and r(CAH eq ) = 1.091(1) Å for the distances and a puckering angle of 28.3(2)°. A comparison of the structural parameters for the axial and equatorial conformers of some monosubstituted cyclobutane would also be of interest to structural scientist which should be obtainable since several such molecules have microwave spectral data reported.…”

High resolution infrared spectroscopy of cyclobutane: A study of vibrational mode coupling involving large amplitude, low frequency modes

“…(4) with 8 was determined to be 0.22 by both IR and microwave work. 30 , 32 , 33 Both 1/lg(q) and V(q) were then expanded to the q 6 term. See Figure 10 for a plot of…”

“…32 , 33 The rocking angle of the CH 2 group is linearly correlated to the puckering angle, 0. 30,32,33 Microwave spectroscopy of the deuterated species resulted in a set of accurate rotational constants for deuterated cyclobutane, in both the ground and excited puckering states. 30 The calculated tunneling splitting was found to be 0.01 cm"1.…”

“…30,32,33 Microwave spectroscopy of the deuterated species resulted in a set of accurate rotational constants for deuterated cyclobutane, in both the ground and excited puckering states. 30 The calculated tunneling splitting was found to be 0.01 cm"1. Combining both the IR and microwave results, leads to the puckering potential shown in Figure 2.…”

Microwave spectra and structural parameters of equatorial-trans cyclobutanol

“…Cyclobutane, c-C 4 H 8 , is a puckered molecule of D 2d symmetry with a microwave determined [1,2] puckered angle r 0 of 28.32 ± 0.23°a nd theoretically predicted values of 29.59° [3] and 29.68° [4]. Monosubstitution of cyclobutane can, therefore, lead to both axial and equatorial conformations.…”