Global Multi-isotopologue fit of measured rotation and vibration-rotation line positions of CO in X1Σ+ state and new set of mass-independent Dunham coefficients

A set of mass-independent U-mj and Delta(mj) parameters globally describing vibration-rotation energy levels of the CO molecule in the X-1 Sigma(+) ground electronic state was fitted to more than 19,000 transitions of (CO)-C-12-O-16, (CO)-C-13-O-16, (CO)-C-14-O-16, (CO)-C-12-O-17, (CO)-C-13-O-17, (LO)-L-12-O-18, and (CO)-C-13-O-18 isotopologues collected from the literature. The maximal values of the vibrational V and the rotational J quantum numbers included in the fit was 41 and 128, respectively. The weighted standard deviation of the fit is .66. Fitted parameters were used for calculation of Dunham coefficients Y-mj for nine isotopologues (CO)-C-12-O-16, (CO)-C-13-O-16, (CO)-C-14-O-16, (CO)-C-12-O-17, (CO)-C-13-O-17, (CO)-C-14-O-17, (CO)-C-12-O-18, (CO)-C-13-O-18, and (CO)-C-14-O-18. Calculated transition frequencies based on the fitted parameters were compared with previously reported. A critical analysis of the CO HITRAN and HITEMP data is also presented. (c) 2012 Elsevier Ltd. All rights reserved.