Knowledge Bank

The diatomic molecules BiN and BiP have been prepared using a laser ablation technique and studied by Fourier transform microwave spectroscopy, in the frequency range 7-22GHz. For BiN only the $J=1-0$ transition fell within this range. Transitions for the ground and first excited vibrational states have been observed for both $Bi14N$ and $Bi15N$. For BiP, which has only one isotopomer, the transitions $J\prime -J\prime \prime =1-0,2-1$ and $3-2$ have been observed, but only for the ground vibrational state. Hyperfine structure has been observed for all nuclei in both molecules; the $\mathrm{<mrow\; data-mjx-texclass="ORD">209</mrow>}Bi$ nuclear quadrupole coupling constants indicate that the electronic structures are similar for the two molecules. Improved bond lengths have been obtained for both molecules.