Diode laser measurements of strengths, half-widths, and temperature dependence of half-widths for CO2 spectral lines near 4.2 μm

Abstract Absolute line strengths have been measured at room temperature for spectral lines in the R branch of the ν3 band of 12C16O2, 12C16O18O, and 12C16O17O and the (ν2 + ν3) − ν2 and (ν1 + ν3) − ν1 bands of 12C16O2 in the region 2365–2393 cm−1 using a tunable diode laser spectrometer; from these measurements band strengths have been computed. Self- and nitrogen-broadened half-widths have been measured for some ν3 lines of 12C16O2 and 12C16O17O, and nitrogen-broadened half-widths measured for some (ν2 + ν3) − ν2 band lines of 12C16O2. From measurements made over a temperature range from 217 to 299 K we have obtained temperature coefficients n, for the N2-broadened Lorentz half-width defined as b L 0 (T) = b L 0 (T 0 )( T T 0 ) −n , for the ν3 and (ν2 + ν3) − ν2 bands of 12C16O2. They are 0.757 ± 0.008 and 0.789 ± 0.015, respectively.

[1]  V. Malathy Devi,et al.  Tunable diode laser spectroscopy of NO2 at 6.2 μm , 1982 .

[2]  G. Plass,et al.  Influence of Doppler Effect and Damping on Line-Absorption Coefficient and Atmospheric Radiation Transfer. , 1953 .

[3]  P. Jansson,et al.  A table of the equivalent widths of isolated lines with combined Doppler and collision broadened profiles , 1968 .

[4]  F. Valero,et al.  Intensities and half-widths at different temperatures for the 201III←000 band of CO2 at 4854 cm−1☆ , 1979 .

[5]  Dudley A. Williams,et al.  Broadening of Infrared Absorption Lines at Reduced Temperatures: Carbon Dioxide† , 1972 .

[6]  Robert H. Hunt,et al.  Lines intensities of the CO2 Σ-Σ bands in the 1.43–1.65 μ region , 1971 .

[7]  Masayuki Tanaka,et al.  Estimation of rotational line widths of carbon dioxide bands , 1969 .

[8]  V. M. Devi,et al.  Temperature dependence of the widths of N2-broadened lines of the nu3 band of 14N16O2. , 1982, Applied optics.

[9]  G. Guelachvili.  High-resolution Fourier spectra of carbon dioxide and three of its isotopic species near 4.3 μm , 1980 .

[10]  G. R. Smith,et al.  Strengths of single lines in the 12C16O2, ν3 band at 4.3 μm , 1980 .

[11]  T. Fujioka,et al.  Measurements of 4.2 μm CO2 pressure broadening by using an HBr chemical laser , 1978 .

[12]  A. T. Young,et al.  Relative intensity calculations for carbon dioxide. IV - Calculations of the partition function for isotopes of CO sub 2. , 1969 .

[13]  A. P. Williams,et al.  Integrated absorption of a spectral line with the Voigt profile , 1974 .

[14]  R. H. Hunt,et al.  Measurement of Line Strengths at Low Pressures—Application to the 2–0 Band of CO , 1968 .

[15]  G. Guelachvili,et al.  R-branch head of the ν3 band of CO2 at elevated temperatures , 1980 .

[16]  H. Hönl,et al.  Über die Intensitäten der Bandenlinien. , 1925 .

[17]  V. Malathy Devi,et al.  Strengths and lorentz broadening coefficients for spectral lines in the ν3 and ν2 + ν4 bands of 12CH4 and 13CH4 , 1983 .

[18]  A Goldman,et al.  AFGL atmospheric absorption line parameters compilation: 1982 edition. , 1981, Applied optics.

[19]  W. Planet,et al.  Temperature dependence of intensities and widths of N2-broadened lines in the 15 μm CO2 band from tunable laser measurements , 1978 .

[20]  Laurence S. Rothman,et al.  Infrared energy levels and intensities of carbon dioxide—II , 1981 .

[21]  J. J. Olivero,et al.  Empirical fits to the Voigt line width: A brief review , 1977 .