High resolution rotational spectroscopy on D2O up to 2.7 THz in its ground and first excited vibrational bending states

Sandra Brünken, Holger S. P. Müller, Christian Endres, Frank Lewen, Thomas Giesen, Brian Drouin, John C. Pearson, Heinrich Mäder
2007 Physical Chemistry, Chemical Physics - PCCP  
We present highly accurate laboratory measurements on the pure rotational spectrum of doubly deuterated water, D 2 O, in selected frequency regions from 10 GHz up to 2.7 THz. Around 140 rotational transitions in both the vibrational ground and first excited bending states (u 2 = 0,1) were measured in total, involving energy levels with unexcelled high J and K a rotational quantum numbers. The data give valuable information for the spectroscopic analysis of this molecule. In the case of the
more » ... he case of the light and non-rigid water molecule, standard methods for its analysis are limited due to large centrifugal distortion interactions. Here, we present a global analysis of rotational and rovibrational data of the u 2 = 0 and 1 states of D 2 O by means of an Euler expansion of the Hamiltonian. In addition to the newly measured pure rotational transitions, around 4000 rotational and rovibrational lines have been included from previous work. It was possible to reproduce the extensive dataset to nearly its experimental uncertainty. The improved predictive capability of the model compared to previous work will be demonstrated.
doi:10.1039/b613925f pmid:17464391 fatcat:3zxm6ecmorarjcngw7h6widbk4