Knowledge Bank

The analysis of the ground state rotational spectrum of $SO2F2a$ has been performed with the Watson's Hamiltonian up to sextic terms but shows some limits due to the A and S reductions. Since $SO2F2$ is a quasi-spherical top, it can also be regarded as derived from an hypothetical $XY4$ molecule. Thus we have developped a new tensorial formalism in the $O(3)\supset Td\supset C2v$ group $chainb$. We test it on the ground state of this molecule using the same experimental $datac$ (0-1 THz region, J up to 99). Both fits are comparable even if the formalisms are slightly different. This talk intends to establish a link between the classical approach and the tensorial formalism. In particular, our tensorial parameters at a given order of the development are related to the usual ones. Programs for spectrum simulation and fit using these methods are named $C2v$ TDS. They are freely available at the URL: http://www.u-bourgogne.fr/LPUB/c2vTDS.html