Knowledge Bank

Alkoxy radicals are important intermediates in combustion and atmospheric chemistry. Alkoxy radicals are also of significant spectroscopic interest for the study of Jahn-Teller and pseudo-Jahn-Teller effects, involving the $X~$ and $A~$ states. Isopropoxy (CH$\mathrm{<mrow\; data-mjx-texclass="ORD">3</mrow>}$CH(O)CH$\mathrm{<mrow\; data-mjx-texclass="ORD">3</mrow>}$) radical is the simplest secondary alkoxy radical. High resolution laser induced fluorescence (LIF) studies of the $B~$ - $X~$ transition have been performed previously. In this talk we will present results obtained from a moderate resolution LIF study of the $B~$ - $A~$ transition whose analysis should complement the $B~$ - $X~$ analysis. The separation between the $A~$ and $X~$ band origin was found to be 58($\pm$3)cm$^{-1}$ which is more precise but consistent with the previous dispersed fluorescence experiment. We are also able to observe transitions corresponding to CO stretch progressions and a low frequency fundamental vibrational mode. The origin band and CO stretch progressions were found to have similar rotational contours which differ from the $B~$ - $X~$ origin band contour. Analysis of the different band contours of $B~$ - $A~$ transitions and their implications will be presented.