Rotational spectrum, ring-puckering vibration and ab initio calculations on tetrahydrothiophene Original Research Article

The rotational spectra of tetrahydrothiophene, c-C4H8S, in the ground state (including spectra of isotopic species) and several excited vibrational states have been reinvestigated in the centimeter and the millimeter wave range up to 300 GHz. Ab initio calculations were performed for structural and conformational analysis, which confirm the experimental values. The low-lying vibrational states were analyzed within the pseudorotation description and from the pseudorotation dependence of the rotational constants the resulting potential energy function was determined.