The absorption spectrum of (C2H2)-C-12 - IV. The regions 7600-9200 cm(1) and 10600-11500 cm(1)

The absorption spectrum of (C2H2)-C-12 has been recorded by intracavity las er absorption spectroscopy (ICLAS) in the 10 600- 11 500 cm(1) spectral reg ion, where no absorption bands were previously reported. Fifteen bands star ting from the vibrational ground state are observed and rotationally analys ed. All corresponding excited vibrational levels were assigned using the po lyad model, the so-called cluster model (El Idrissi, M.I., Lievin, J., Camp argue, A., and Herman, M., 1999, J. chem. Phys., 110, 2074) which allows vi brational energies, rotational B-V constants and, to some respect, relative band intensities to be predicted. Additional data and constants are also p rovided in the range 7600-9200 cm(1), whenever improving the literature res ults, from spectra recorded previously at ULB using Fourier transform spect roscopy. The assignment procedure in the range recorded by ICLAS is detaile d, leading to a deeper understanding of vibration-rotation and intensity fe atures of the absorption bands within the frame of the cluster model.