Knowledge Bank

Stark measurements of the dipole moments in excited states of hafnium mono-sulfide, $\mathrm{<mrow\; data-mjx-texclass="ORD">180</mrow>}Hf,32S$, and hafnium mono-oxide, $\mathrm{<mrow\; data-mjx-texclass="ORD">180</mrow>}Hf16O$, have been performed. The molecules were produced using a laser ablation source combined with a time-of-flight mass spectrometer, where a static electric field was applied. From the first order Stark effect splitting the permanent electric dipole moments, $\mu$, were determined to be 3.416(23) D and 3.478(25) D for the HfS $D1\Pi v=0$ and $v=1$ states, respectively, and 2.665(29) D for the HfO $b3\Pi 1v=0$ state. The e- and f-parity mixing due to the Stark effect was examined. Field-free low temperature spectra for the (0,0), (1,0), and (2,0) b ands of the $D1\Pi -X\mathrm{<mrow\; data-mjx-texclass="ORD">1</mrow>}\Sigma +$ transition of HfS and the (0,0) b and of the $b\mathrm{<mrow\; data-mjx-texclass="ORD">3</mrow>}\Pi 1-X\mathrm{<mrow\; data-mjx-texclass="ORD">1</mrow>}\Sigma +$ transition of HfO were recorded and analyzed. Term-value calculations were performed, including most previously reported spectra, and potential energy curves and sets of molecular parameters were extracted.