High-resolution infrared action spectroscopy of the fundamental vibrational band of CN+

Abstract Rotational-vibrational transitions of the fundamental vibrational modes of the 12 C 14 N+ and 12 C 15 N + cations have been observed for the first time using a cryogenic ion trap apparatus with an action spectroscopy scheme. The lines P ( 3 ) to R ( 3 ) of 12 C 14 N + and R ( 1 ) to R ( 3 ) of 12 C 15 N + have been measured, limited by the trap temperature of approximately 4 K and the restricted tuning range of the infrared laser. Spectroscopic parameters are presented for both isotopologues, with band origins at 2000.7587(1) and 1970.321(1) cm-1, respectively, as well as an isotope independent fit combining the new and the literature data.