Knowledge Bank

High resolution spectra of the $[14.6]2\Delta 5/2-X2\Delta 5/2(9.0)$ band of Nil near $16594cm-1$ have been observed under jet-cooled condition following the reaction of laser ablated nickel metal with $CH3I$. With a line width of around 70 MHz, the hyperfine structure is partially resolved. Since the $\mathrm{<mrow\; data-mjx-texclass="ORD">58</mrow>}$Ni atom has nuclear spin I = 0, the hyperfine structure arises from the iodine atom, which has a nuclear spin of 5/2. Both $\mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>}\Delta 5/2$ states conform to case $a\beta$ coupling scheme. Molecular constants for both the upper and lower $\mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>}\Delta 5/2$ states will be reported.