Knowledge Bank

The rovibrational transitions in the low frequency bending (vdW) mode of the intermolecular hydrogen bond in the OCO-HF cluster have been observed by millimeter-wave and submillimeter-wave spectroscopy combined with pulsed supersonic jet expansion technique. In this study, we observed 30 line belonging to the $\nu \prime =11-00$ band in the frequency region from 260 to 320 GHz, where $\nu \prime$ denotes quanta of OCO-HF skeltal bend excitation with l units of vibrational angular momentum. The observed spectra were analyzed with a linear molecule Hamiltonian and the band origin is determined to be $272548.8016(49)MHz$. We also detected several lines of the P-branch transitions of the $\nu bend\prime =22-11$ hot band.