Analysis of the Comet-Tail (A2Π –X2Σ+) Bands of 13C16O+

The interaction in CO+: Deperturbation analyses of B–A and A–X bands of 12C16O+, 13C16O+ and 14C16O+

“…However, a detailed examination of the fitted A-state parameters (B t , D t , A t , A Dt , p t , q t ) reveals numerous examples where deviations from the expected smooth vibrational dependences are many times the estimated parameter uncertainties. In the case of 13 CO + , for example, the fitted values [22] of A t for t = 5 and 7 are clearly not consistent with the relatively smooth vibrational dependence for t 6 4. In the present work, we show that such anomalies occur because of interactions between the t A -level and one or more t X levels that are far from being neardegenerate.…”

“…As in our other recent analyses [20,22] of bands in the A 2 P ! X 2 R þ Comet Tail system of CO + , emission spectra were excited using an air-cooled hollow cathode discharge tube.…”

“…However, even in the most recent and more reliable studies of CO + A ? X spectra [20,22,24], the fitted values of several parameters, such as p t , q t and even A t , do not exhibit a smooth tdependence; deviations from smooth behavior are much larger than the associated standard errors. Fig.…”

“…Thus we have refitted all the data of Refs. [20,22,24] with explicit account of such interactions (and with the same criteria for blended branches described in Section 3.2). When two t à X levels are involved, the expanded 4  4 matrix of Table 1 is employed, with the two perturbers denoted as t* and t**.…”

“…Except for the six perturbed levels analyzed in Section 3.2, the results of Refs. [22,22,24] are plotted. The associated error bars are much smaller than the size of the symbols in the plots.…”