We present experimental studies of reactions of doubly charged carbon cation (carbon dication, C2+, C III) with O-2, N-2, CO, and HD molecules. A temperature-variable cryogenic linear 22-pole radio frequency ion trap was employed to obtain reaction rate coefficients and their temperature dependencies in the range from 40 to 300 K.
The measured coefficients are almost independent of the temperature at the covered range. At 60 K the reaction rate coefficients are 1.4(3) x 10(-9) cm(3) s(-1) for O-2, 1.9(4) x 10(-12) cm(3) s(-1) for N-2, 8(2) x 10(-12) cm(3) s(-1) for CO, and 1.5(5) x 10(-10) cm(3) s(-1) for HD.