Infrared spectroscopy of radioactive hydrogen chloride H36Cl

We present the first report of optical absorption spectroscopy of (HCl)-Cl-36, a radioactive isotopologue of hydrogen chloride. We used Fourier-transform infrared spectroscopy to determine the line center wavenumbers of the fundamental rovibrational band lines P(10)-R(10) and the first overtone band lines P(1)-R(7) with total uncertainty of less than 0.0018 cm(-1) (60 MHz) and 0.007 cm(-1) (0.2 GHz), respectively, at 68% confidence level. We also performed a rotational analysis on the bands to determine the related molecular constants. We further compared the linewidths and relative intensities of the lines to those of the stable isotopologues (HCl)-Cl-35 and (HCl)-Cl-37. The new spectroscopic information assists in developing optical instrumentation for the detection of (HCl)-Cl-36. (C) 2021 The Authors. Published by Elsevier Ltd.Peer reviewe