Department of ChemistryTrans-1,3-butadiene was investigated by Correlated Rotational Alignment Spectroscopy (CRASY) in which pure rotational Raman information coupled to ion mass information. The rotational Raman spectra with a broad spectral bandwidth of 500 GHz were calibrated to a GPS stabilized external clock that enhanced the high accuracy in rotational constants. . Opto-mechanical delay stage, sparse sampling and pulse jumping settled CRASY into high resolution spectroscopic regime. We performed an analysis of the gas-phase rotational Raman spectrum of butadiene (BD) and its most abundant isotopologues of 1-13C-BD and 2-13C-BD. In this work, we advanced an order of magnitude better rotational constants for main BD isotope. The rotational constants of pure 2-13C-BD were also revealed for the first time.clos
