Absolute IR intensities of the .nu.1 bands of hydrodinitrogen(1+) and oxomethylium determined by direct laser absorption spectroscopy in fast ion beams

The authors report the determination of absolute integrated band intensities (S{sub v}{sup 0}) for the {nu}{sub 1} fundamental bands of HN{sub 2}{sup +} and HCO{sup +} by the recently developed technique of direct laser absorption spectroscopy in fast ion beams. The values obtained for HN{sub 2}{sup +} (1,250 (300) cm{sup {minus}2} atm{sup {minus}1}) and HCO{sup +} (430 (100) cm{sup {minus}2} atm{sup {minus}1}) are substantially lower than corresponding results from high level ab initio calculations.