Knowledge Bank

Rotational spectrum of the $\mathrm{<mrow\; data-mjx-texclass="ORD">24</mrow>}Mg35Cl$ radical in its $X2\Sigma$ state has been measured using a Fourier-transform microwave spectrometer combined with a laser-ablation source. A Q-switched Nd:YAG laser (532 nm) was used to vaporize Mg atoms form a target rod located in the throat of a pulsed valve. The radical was produced by the reaction of ablated Mg with $Cl2$ diluted in Ar inside a $5mm\varphi$ channel of 10 mm in length, and then pulsed through in a supersonic expansion. The $N=1-0$ transitions with fully-resolved hyperfine structure, observed at -14 GHz for the vibrational ground and the first excited states, were analyzed to derive accurate sets of spectroscopic constants, in combination with the previously reported data in the millimeter-wave $region.1$ The spin-density distribution and the ionic character have been evaluated from the precisely determined magnetic hyperfine coupling and $eQq$ constants associated with the $\mathrm{<mrow\; data-mjx-texclass="ORD">35</mrow>}Cl$ nucleus.