High-resolution analysis of the $\hat{I}{½}_3$ band of radiocarbon methane ${}^{14}C{H}_4$

Abstract

We present the first high-resolution measurements and rotational analysis of the fundamental asymmetric stretching vibrational band $\hat{I}{½}_3(F_2)$ of radiocarbon methane. A spectrometer consisting of a mid-infrared continuous-wave optical parametric oscillator and a cantilever-enhanced photoacoustic detector was employed to determine the wavenumbers of 43 rovibrational lines. A spectroscopic model could reproduce all the observed transition wavenumbers within the accuracy of the experiment. Our work contributes to the development of radiocarbon methane detectors based on laser spectroscopy.