Rotational line strengths and self-pressure-broadening coefficients for the 1.27-μm, a 1Δg-X3Σg-, v = 0-0 band of O2

We measured at 296 K the rotational line strengths and pressure-broadening coefficients for the 1.27-mu m, a (1) Delta(g)-X-3 Sigma(g)(-), upsilon = 0-0 band of O-2 with a Fourier transform infrared spectrometer using an optical path length of 84 m, a spectral resolution of 0.01 cm(-1), and sample pressures between 13 and 104 kPa. The integrated band strength is 7.79(17) x 10(-6) m(-2) Pa-1 [7.89(17) x 10(-5) cm(-2) atm(-1)], and the Einstein A coefficient for spontaneous emission is 2.237(51) x 10(-4) s(-1), which corresponds to an upper-state 1/e lifetime of 1.24(3) h. The pressure-broadening coefficients decrease with increasing N and range from 19 to 38 MHz/kPa (FWHM). The mean value for the transitions studied is 30.3(21) MHz/kPa [0.1024(71) cm(-1)/atm] (FWHM). The Einstein A coefficient determined here is in good agreement with the widely accepted value of 2.58 x 10(-4) s(-1) initially obtained by Badger et al. [J. Chem. Phys. 43, 4345 (1965)] more than 30 years ago. The standard uncertainties given above are one standard deviation.