Conformational Isomerism of 1-Iodopentane

The spectra of 1-iodopentane were collected initially using a CP-FTMW spectrometer. Ab initio calculations were carried out to predict which conformers are present in the gas phase. In an expansion of argon, we observed the GAA, AAA, GGA conformers of 1-iodopentane. Further data was then collected on a BF-FTMW to obtain transitions from specific regions. Based on the equation for Ray's asymmetry parameter [1], the three conformers of 1-iodopentane are determined to be prolate asymmetric type rotors: ?(GAA) = -0.98, ?(AAA) = -1.0, and ?(GGA) = -0.95. Furthermore, as iodine has a nuclear spin I = 5/2 [2], which induces hyperfine structure in the rotational spectrum, hyperfine splittings have been observed in the microwave spectra of this study.