The 583.2 GHz torsional hot-band of (D2O)3

Abstract

We report the observation of a new c-type band of (D2O)3 at 583.215 92(37) GHz, which we assign to the k=±20←±10 torsional hot-band. The new data includes the first observation of K=0 states for the k=+10 and k=−20 levels and effects a correct assignment of these states. A new perturbation was observed for the K=2 states of the k=+20←−10 subband splitting each transition into two equally spaced equal intensity doublets. Analysis of the band and inclusion into a global fit of all torsional bands produces negligible differences with previous analyses, and confirms the validity of the Hamiltonian developed to treat the coupling between torsional motion and overall rotation. The 583.2 GHz band completes the precise characterization of all (D2O)3 vibrational levels below 100 cm−1.