VIS and VUV spectroscopy of ¹²C¹⁷O and deperturbation analysis of the A¹Π, υ = 1–5 levels

Abstract

P and perturber states were described in terms of a set of deperturbed molecular constants, spin-orbit and L-uncoupling interaction parameters, equilibrium constants, 309 term values, as well as isotopologue-independent spin-orbit and rotationelectronic perturbation parameters.

Perturbations in the A1Π,v= 0 state of12C18O investigated via complementary spectroscopic techniques

“…The discharge glow was focused by a plano-convex quartz lens onto the entrance aperture (1.0 mm diameter) of a 1.71 m Fourier-transform (FT) spectrometer [28,30]. A recent modification of this spectrometer significantly reduced the reflection of the HeNe laser beam, used for calibration and control of the position of a movable retroreflecting mirror, from optical elements in the interferometer and detector compartments, and noticeably improved its sensitivity in the VIS and UV regions.…”

“…The general methodology of this work is similar to our recent studies of other CO isotopologues [28][29][30]. Three spectroscopic techniques are employed: Doppler-free two-photon laser spectroscopy of the A The first technique provides transition frequencies with ultrahigh accuracy and the latter two provide highresolution broadband measurements.…”

“…Conversely, the level crossings of A(0) and D(0) occur at higher J for higher mass because of the smaller vibrational constant, ω e , of D 1 . To quantify the interaction energies and deperturbed molecular constants of all directly and indirectly observed levels we employ the same methodology as Niu et al [25] and Hakalla [30] applied to other isotopologues. We used 476 transition frequencies obtained from the laser, VIS-FT and VUV-FT studies of A−X(0, 0), B−A(0, 0) and B−X(0, 0) transitions and their satellite extra lines.…”

Spectroscopy and perturbation analysis of the A1π (v=0) state of 13 C16 O

“…The B 1 + −A 1 (0, 0) band was measured in the emission from a water-cooled hollow-cathode discharge lamp with two anodes that has been used and described in recent years for a number of investigations of the visible spectra of theÅngström [36] and Herzberg bands [37] for CO isotopologues. The discharge lamp undergoes a preparation phase depositing either 12 C or 13 C atomic isotopes onto the electrodes after which the oxygen containing isotope of choice is then introduced and a DCplasma formed by applying a potential (650 V) onto the anodes.…”

“…Their perturbative effects are expected to be significant but could not be independently estimated because of strong correlations with the A 1 (0) band origin parameter, T v . Their interaction energies were then deduced from isotope-independent perturbation parameters originally based on experimental work in other isotopologues [36,43] and adapted to interacting levels in our 13 C 16 O model by calculating the relevant isotope-dependent vibrational-overlap factors, as described in Hakalla et al [36].…”