ABSTRACT
Transmittance curves on pure nitric acid vapor have been determined at CO laser frequencies of 1661.8833 cm(-1), 1693.9957 cm(-1), and 1711.6199 cm(-1). Voigt profile analyses for the first and third frequencies give, respectively, alpha = (2.02 +/- 0.72) x 10(-4) Torr(-1) cm(-1), Delta = (1.63 +/- 0.33) x 10(-3) cm(-1) , E(nu(o)) = (0.668 +/- 0.302) X 10(-2) Torr(-1) cm(-1); alpha = (8.95 +/- 0.27) x 10(-4) Torr(-1) cm(-1), Delta = (1.64 +/- 0.33) x 10(-3) cm(-1), E(nu(o)) = 0.327 +/- 0.140 Torr(-1) cm(-1). Here alpha is the broadening parameter, Delta the frequency offset, and E(nu(0)) the extinction coefficient at line center in the Doppler region. Application of the Galatry profile gives the same results as well as a self-diffusion coefficient consistent with the value 0.057 cm(2)/sec from kinetic theory. Finally, the foreign gas broadening parameter with respect to nitrogen is determined as B = 0.997 +/- 0.245 at 1661.8833 cm(-1) and B = 5.91 +/- 0.78 at 1711.6199 cm(-1) .
