Knowledge Bank

Absolute line strengths have been measured, at room temperature, for R branch spetral lines of the $\nu 3bands$ of $\mathrm{<mrow\; data-mjx-texclass="ORD">12</mrow>}C16O18O$ and $\mathrm{<mrow\; data-mjx-texclass="ORD">12</mrow>}C16O17O$, and for the $(\nu 2+\nu 3)-\nu 2$, and $(\nu 1+\nu 3)-\nu 1$ bands of $\mathrm{<mrow\; data-mjx-texclass="ORD">12</mrow>}C16O2$, in the $2365-2393cm-1$ spectral region using a tunble diode laser. Self- and nitrogen-broadened half-widths were measured for some of the $\nu 3$ lines of $\mathrm{<mrow\; data-mjx-texclass="ORD">12</mrow>}C16O2$ and $\mathrm{<mrow\; data-mjx-texclass="ORD">12</mrow>}C16O17O$. Nitrogen-broadened half-widths were measured for the $(\nu 2+\nu 3)-\nu 2$ lines of $\mathrm{<mrow\; data-mjx-texclass="ORD">12</mrow>}C16O2$.From half-width measurements made on nitrogen-broadened lines over a temperature range from 217 to 299K we have calculated the temperature coefficient of the Lorentz half-width n, defined as $bL\circ (T)=bL\circ (To)(T/To)-n$, for the $\nu 3$ and $(\nu 2+\nu 3)-\nu 2$ bands of $\mathrm{<mrow\; data-mjx-texclass="ORD">12</mrow>}C16O2$. The mean values of the n are $0.757\pm 0.008$ and $0.789\pm 0.015$, respectively. The band strengths deduced form line strengths for both the $\nu 3$ and $(\nu 2+\nu 3)-\nu 2$ bands of $\mathrm{<mrow\; data-mjx-texclass="ORD">12</mrow>}C16O2$ are about 5% lower than those of the latest AFGL line listing. Isotopic band strengths for the $\nu 3$ bands are also reported.