x-y Coriolis interaction in the ν5 and ν8 bands of propyne-d3

High resolution Fourier transform spectra of the ν 5 and ν 8 bands of CD 3 C≡CH have been recorded and analyzed taking into account the strong x-y Coriolis interaction between these fundamentals. Fermi resonance of the ν 8 state with the ν 9 + ν 10 state, l-type doubling interaction between the ± l components of ν 8 and a weak k-type doubling interaction between the ν 5 and ν 8 states have also been included in the perturbation treatment. The parameters of the ν 5 and ν 8 states as well as some of the parameters of the unobserved ν 9 + ν 10 state have been determined. An estimate of the relative value of the transition moments has been obtained from the line intensities, which are strongly affected by the x-y Coriolis interaction.