Fourier-transform spectroscopy of 13C17O and deperturbation analysis of the A1Π (υ=0–3) levels

Abstract The high-resolution B 1 Σ + →A 1 Π (0, 0) and (0, 3) emission bands of the less-abundant 13 C 17 O isotopologue have been investigated by Fourier-transform spectroscopy in the visible region using a Bruker IFS 125HR spectrometer at an accuracy 0.003 cm -1 . These spectra are combined with high-resolution photoabsorption measurements of the 13 C 17 O B 1 Σ + ←X 1 Σ + (0, 0), B 1 Σ + ←X 1 Σ + (1, 0) and C 1 Σ + ←X 1 Σ + (0, 0) bands recorded with an accuracy of 0.01 cm -1 using the vacuum ultraviolet Fourier-transform spectrometer, installed on the DESIRS beamline at the SOLEIL synchrotron. In the studied 17,950–22,500 cm -1 and 86,800–92,100 cm -1 regions, 480 transitions have been measured. These new experimental data were combined with data from the C→A and B→A systems, previously analyzed in 13 C 17 O. The frequencies of 1003 transitions derived from 12 bands were used to analyze the perturbations between the A 1 Π ( υ =0–3) levels and rovibrational levels of the d 3 Δ i , e 3 Σ - , a' 3 Σ + , I 1 Σ - and D 1 Δ states as well as to a preliminary investigation of weak irregularities that appear in the B 1 Σ + ( υ =0) level. Deperturbed molecular constants and term values of the A 1 Π state were obtained. The spin-orbit and L -uncoupling interaction parameters as well as isotopologue-independent spin-orbit and rotation-electronic perturbation parameters were derived.