Knowledge Bank

In continuation of previous $work,1,2$ the infrared emission and absorption of heated carbon dioxide, enclosed in a special gas cell, have been measured at temperatures from $25\circ$ to $1000\circ C$ and at pressures up to 1000 mm Hg. Spectral absorptivities and absorption coefficients were calculated from spectrum tracings of the $4.3\nu$ fundamental band and the $2.7\nu$ combination bands, at concentrations up to 17 cm-atm. Saturation with respect to partial pressure, temperature, and total pressure was observed over most of the spectrum. A semiquantitative picture was obtained of the relation between temperature and the molecular spectral energy distribution.