Towards Realization of Reactive Gas Amount of Substance Standards Through Spectroscopic Measurements

This paper discusses the use of high-precision direct absorption spectroscopy to realize the amount of substance standards for ozone (O 3), a reactive species which cannot be delivered through traditional gravimetrically based gas cylinder standards. The O3 amount of substance is linked to the known concentrations of nitric oxide (NO) and nitrogen dioxide (NO2) through a gas-phase titration reaction and spectroscopic measurements using room-temperature pulsed quantum-cascade lasers. Ultimately, this approach will allow the determination of an O3 transition line strength linked to the primary gravimetric standards of NO and NO 2. The line strength can be used in future measurements to determine O3 concentrations of unknown samples