The Infra-Red Spectrum and Molecular Constants of C12O16 and C13O16

Abstract

The infra-red spectrum of carbon monoxide has been investigated with a 7200 line-per-inch grating. The fundamental bands of ${\mathrm{C}}^{12}$ ${\mathrm{O}}^{16}$ and ${\mathrm{C}}^{13}$ ${\mathrm{O}}^{16}$ and the overtone of ${\mathrm{C}}^{12}$ ${\mathrm{O}}^{16}$ were measured. The rotational structure has been analyzed by means of combination relations, and the following new values of the molecular constants have been obtained: ${\omega }_e=2169.60\mathrm{}$ ${\mathrm{cm}}^{-1\mathrm{}}$, ${{\omega }_e}^{\prime }=2121.33\mathrm{}$ ${\mathrm{cm}}^{-1\mathrm{}}$, $x_e{\omega }_e=13.22\mathrm{}$ ${\mathrm{cm}}^{-1\mathrm{}}$, ${\left(x_e{\omega }_e\right)}^{\prime }=12.64\mathrm{}$ ${\mathrm{cm}}^{-1\mathrm{}}$, $B_e=1.9238\mathrm{}$ ${\mathrm{cm}}^{-1\mathrm{}}$, ${B_e}^{\prime }=1.8465\mathrm{}$ ${\mathrm{cm}}^{-1\mathrm{}}$, $\alpha =0.0175\mathrm{}$ ${\mathrm{cm}}^{-1\mathrm{}}$, ${\alpha }^{\prime }=0.0169\mathrm{}$ ${\mathrm{cm}}^{-1\mathrm{}}$, $I_e=14.548\mathrm{}\times {10}^{-40\mathrm{}}$ g ${\mathrm{cm}}^2$, ${I_e}^{\prime }=15.157\mathrm{}\times {10}^{-40\mathrm{}}$ g ${\mathrm{cm}}^2$, $r_e$ (average for both molecules) = 1.1291×${10}^{-8\mathrm{}}$ cm. The primed constants refer to the isotopic molecule.