Knowledge Bank

The $a1\Delta g$$\leftarrow$$X3\Sigma g-$ system of the $\mathrm{<mrow\; data-mjx-texclass="ORD">16</mrow>}$O$\mathrm{<mrow\; data-mjx-texclass="ORD">17</mrow>}$O, $\mathrm{<mrow\; data-mjx-texclass="ORD">17</mrow>}$O$\mathrm{<mrow\; data-mjx-texclass="ORD">18</mrow>}$O and $\mathrm{<mrow\; data-mjx-texclass="ORD">17</mrow>}$O$\mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>}$ isotopologues of oxygen was studied by high sensitivity CW-Cavity Ring Down Spectroscopy. The spectra of a $\mathrm{<mrow\; data-mjx-texclass="ORD">17</mrow>}$O highly enriched sample were recorded at room temperature between 7640 and 7917 \wn~and at liquid nitrogen temperature in the 7876-7893 \wn~ region. The magnetic dipole (0-0) band was observed for all three $\mathrm{<mrow\; data-mjx-texclass="ORD">17</mrow>}$O-containing isotopologues. At liquid nitrogen temperature some of the transitions were observed with partially resolved hyperfine splitting due to the $\mathrm{<mrow\; data-mjx-texclass="ORD">17</mrow>}$O nuclear spin, allowing determination of the hyperfine constants. The electric quadrupole (0-0) band and the (1-1) magnetic dipole hot band were also observed for the $\mathrm{<mrow\; data-mjx-texclass="ORD">16</mrow>}$O$\mathrm{<mrow\; data-mjx-texclass="ORD">17</mrow>}$O and $\mathrm{<mrow\; data-mjx-texclass="ORD">17</mrow>}$O$\mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>}$ species. The rotational and hyperfine spectroscopic parameters of the $X3\Sigma g-$ and $a1\Delta g$ states of the three studied isotopologues were derived from global fit of the measured line positions and microwave and Raman measurements available in the literature. The rotational constants of the $a1\Delta g$ (v=0, 1) states of $\mathrm{<mrow\; data-mjx-texclass="ORD">17</mrow>}$O$\mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>}$ are determined for the first time.