Knowledge Bank

The recent report of the rotational spectrum of He-OCS by Higgins and $Klemperera$ encouraged us to search for transitions of He-containing van der Waals complexes with our pulsed molecular beam Fourier transform microwave spectrometer. It was possible to measure additional transitions of the normal isotopomer and the previously unobserved spectra of several rarer isotopomers of He-OCS, including $He-OC34S,He-O13CS$, and $He-OC33S,33S$ nuclear quadrupole hyperfine structure could be resolved and analyzed in case of $He-OC33S$. Spectra of two further He-molecule complexes, i.e. $He-COb$ and $He-CO2,c$ will also be presented. For He-CO, transitions of the rarer isotopomers $He-C18O$, and $He-13CO,He-13C18O$, and $He-13C17O$ were also measured. In the case of $He-CO2$ it was possible to detect transitions of three more istopomers, i.e. $He-13CO2,He-18O13CO$, and $He-17OCO$. For both $\mathrm{<mrow\; data-mjx-texclass="ORD">17</mrow>}O$ containing complexes, the $\mathrm{<mrow\; data-mjx-texclass="ORD">17</mrow>}O$ nuclear quadrupole hyperfine structures were detected and analyzed.