Knowledge Bank

Spectroscopic data for the ground and low-lying states HfS$\mathrm{<mrow\; data-mjx-texclass="ORD">+</mrow>}$ have been obtained using the technique of pulse field ionization - zero electron kinetic energy (PFI-ZEKE) spectroscopy. PFI-ZEKE spectra were recorded for the levels X$\mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>}$\Sigma$\mathrm{<mrow\; data-mjx-texclass="ORD">+</mrow>}$ (v=0-18), $\mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>}$\Delta$\mathrm{<mrow\; data-mjx-texclass="ORD">5<mrow\; data-mjx-texclass="ORD">/</mrow>2</mrow>}$ (v=0-8) and $\mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>}$\Delta$\mathrm{<mrow\; data-mjx-texclass="ORD">3<mrow\; data-mjx-texclass="ORD">/</mrow>2</mrow>}$ (v=0-3). Assignments of the electronically excited states of HfS$\mathrm{<mrow\; data-mjx-texclass="ORD">+</mrow>}$ are based on CCSD(T) and DFT calculations with SDB-aug-cc-pVTZ basis set. Rotationally resolved spectra were recorded for the X$\mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>}$\Sigma$\mathrm{<mrow\; data-mjx-texclass="ORD">+</mrow>}$ (v=0) state using single rotational line excitation of the intermediate state. The ionization energy for HfS, term energies and molecular constants for the ground and low-lying states of HfS$\mathrm{<mrow\; data-mjx-texclass="ORD">+</mrow>}$ will be reported.