Submillimeter microwave spectrum and spectroscopic constants of the OCS molecule. Isotopic species 16O 12C 33S and 18O 12C 32S
Microwave spectra of 16O 12C 33S and 18O 12C 32S in their natural isotopic abundances were investigated in the range 280-510 GHz. The effective rotational and centrifugal constants have been determined for all observed vibrational states. An analysis of the rotational spectrum taking account of l- and Fermi-resonances has been performed within each isotopic species.