Singular value decomposition based broadband microwave spectroscopy of 1H,2H-perfluorocyclobutane

Broadband rotational free induction decays (FIDs) from 1H,2H-perfluorocyclobutane have been captured at a rate of 25 ps/point for a duration of 20 μs. FIDs have been treated using fast Fourier transformation (FFT) and singular value decomposition (SVD). It is demonstrated that the SVD-based model can yield a sufficient number of accurate transition frequencies for initial spectral analysis using only ≈1% (200 ns) of the FID. Furthermore, the SVD-based analysis has produced information concerning transition phase, amplitude, damping, and frequency for the strongest molecular signals. The damping factors determined appear useful in distinguishing molecular and non-molecular signals. The FFT analysis of the full FID has yielded, for the first time, spectroscopic parameters for the parent and all C-13 isotopologues of both the cis and trans species.