Morphed intermolecular potential of OC:HCCH complex based on infrared quantum cascade laser spectroscopy

Spectroscopic studies of the OC:HCCH complex are reported using a continuous supersonic slit jet spectrometer with broadband frequency mode-hop free tunable infrared quantum cascade lasers (QCL), centered at 4.4 and 4.6 μm. This Letter includes an extended analysis of the ν3 CO stretching vibration frequency, and investigation of the ν3 + ν91 − ν91 hot band, the ν3 + ν91 and ν3 + ν81 combination bands for OC–HCCH. The ground state low frequency bend, ν91, is determined at 20.48361(20) cm−1. The generated rovibrational data is incorporated with previously determined information and used to generate a four-dimensional compound-model morphed potential with radial correction, giving further insight into the molecular dynamics of this complex.