Temperature evaluation of UF6 and cluster detection in nozzle expansion using low-resolution infrared absorption spectroscopy

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and mixtures of UF₆ with argon and nitrogen through a bidimensional nozzle was studied using low-resolution infrared spectroscopy in the ν₃ absorption band region. The experiments were carried out in order to calculate the molecular temperature of the beam and also to verify cluster formation in the expansion. The molecular beam temperature evaluation was based on the measurements of the low-resolution bandwidth, which were compared to simulated spectra results. The temperatures were also evaluated using the measured pressure at the end of the nozzle by a pitot tube. In the conditions where no cluster formation was observed the calculated theoretical temperatures using an equilibrium expansion model are in good agreement with the data obtained through the analysis of the experimental spectra and through the pitot tube pressure measurement. Cluster formation was observed for temperatures below about 120 K. In these conditions the infrared spectra showed shoulders in the region above 630 cm^-1 and a shoulder or band between 616 and 600 cm^-1.