Knowledge Bank

Microwave and radiofrequency spectra for the $Ar\cdot H2S$ molecule and its deuterated analogs have been determined by electric resonance spectroscopy of supersonic argon beams seeded with $H2S$. Precise results for (B+C)/2, (B-C)/2, $\mu a,(\mu b\mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>}+\mu c\mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>})1/2$ and for nuclear hyperfine interactions have been obtained and will be discussed. One of the most striking results is the small $\mu a$ value for $Ar\cdot H2S$ (0.186 D) and $Ar\cdot D2S(0.17D)$, while the apparent perpendicular electric dipole moment $(\mu b\mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>}+\mu c\mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>})1/2$ is 0.8 D for $Ar\cdot H2S$. An hypothetical rigid, linear hydrogen-bonded complex would have $\mu a$ and the perpendicular moment both equal to 0.68D to a first approximation. These results suggest that even in the equilibrium configuration, this molecule is not hydrogen--bonded.