Absorption cross-sections of NO 2: simulation of temperature and pressure effects

Abstract

The measurements of the NO 2 absorption cross sections by several authors have been considered in order to derive its temperature and pressure dependences in the 13 200– 42 000 cm −1 spectral range. The temperature dependence is assumed to be linear in the temperature range investigated (217.0– 298.5 K ), whereas the influence of the total pressure is expressed as a temperature-dependent broadening coefficient. From measurements performed with mixtures of NO 2 in air and in N 2, values of γ air 0 (296 K) and γ N 2 0 (296 K) were found to be, respectively, 0.081±0.002 and 0.069±0.003 cm −1 atm −1 . The temperature coefficient n obtained in the present work is 0.8±0.1. The parameterization of the cross sections developed in this work can reproduce measured cross sections within 4%.