Knowledge Bank

The absorption spectra of yttrium and nickel monoiodides at vwavelength between 445-510 nm have been investigated using the technique of laser vaproization/reaction with free-jet expansion of cavity ring-down laser absorption (CRLA) spectroscopy. Yttrium monoiodide molecule was produced by reacting laser-ablated yttrium or nickel atoms and methyl iodide seeded in helium. For the YI molecule, several bands of the $D1\Pi -X1\Sigma +$ transition were observed and vibrational levels were analyzed. For NiI, two new transition systems were recorded and analyzed, namely the [21.3] $2Delta5/2-X2\Delta 5/2$ and [21.9] $2Delta3/2-X2\Delta 5/2$ system. Spectra of both $\mathrm{<mrow\; data-mjx-texclass="ORD">58</mrow>}$NiI and $\mathrm{<mrow\; data-mjx-texclass="ORD">60</mrow>}$NiI isotopic molecules were observed. Equilibrium molecular constants for both electronic states are reported and the equilibrium bond length was respectively determined to be 2.431\AA for the [21.3]$2\Delta 5/2$ state and 2.481\AA for the [21.9]$2\Pi 3/2$ state.