Knowledge Bank

A Balle-Flygare FT-MW spectrometer coupled to a laser ablation source has been used to measure the pure rotational spectra of H$\mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>}$O$\cdots$AgF. Generation is via laser ablation (532 nm) of a silver rod in the presence of SF$\mathrm{<mrow\; data-mjx-texclass="ORD">6</mrow>}$, argon, a low partial pressure of H$\mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>}$O and the molecules are stabilized by supersonic expansion. The spectra of eight isotopologues have been measured. Rotational constants, $B0$ and $C0$, and the centrifugal distortion constant, \Delta have been determined. Isotopic substitutions are available at the silver, oxygen and hydrogen atoms. The spectra are consistent with a linear arrangement of oxygen, silver and fluorine atoms and the structure is either $C2v$ planar at equilibrium or $CS$ pyramidal but with a low potential-energy barrier to planarity such that the v = 0 and 1 states associated with the motion that inverts the configuration at the O atom are well separated.