12C16O2 in emission in the 4.5-μm region:: Transitions v1vl2v3→v1vl2(v3-1) with (2v1+v2)=6 occurring between highly excited vibrational states

Eight emission spectra of CO2 + N-2 mixtures excited by de discharge were recorded using a Fourier Transform Spectrometer (Bruker Spectrometer 120HR) with a resolution of 0.003 cm(-1) in the 4.5-mu m region. Results (wavenumbers, band centers, spectroscopic constants) concerning 13 new vibrational transitions which have not been observed earlier and which occur between highly excited levels (hence their very small population) are reported. The derived spectroscopic parameters allow the reproduction of the experimental wavenumbers with a RMS < 3 x 10(-4) cm(-1). (C) 1998 Academic Press.