RATE CONSTANTS FOR THE REACTION OF AR+(2P3 2) WITH N2 AS A FUNCTION OF N2 VIBRATIONAL TEMPERATURE AND ENERGY-LEVEL/

Rate constants have been measured for the reaction of Ar+ (P-2(3/2)) w ith N2 as a function of N2 vibrational temperature for a rotational an d translational temperature of 300 K. The rate constants increase from a value of 1.2 x 10(-11) cm3 s-1 at a N2 vibrational temperature of 3 00 K to 2.0 X 10(-10) cm3 s-1 at a N2 vibrational temperature of 4700 K. The data are used to derive rate constants for specific vibrational levels. The rates constants for v = 0-3 are 1.2 X 10(-11), 3.0 X 10(- 10), 7.6 X 10(-10), and 7.6 X 10(-10) cm3 s-1, respectively. Additiona lly, the data suggest that the rate constant for v > 3 drops from the v = 3 value, although this is less certain. The increase in the rate c onstants with increasing v is postulated to arise from the N2(V) --> N 2+ (v + 1) channel becoming less endothermic with increasing v and the refore closer to being resonant: Vibrational energy is found to be mor e effective at promoting this reaction than are translational or rotat ional energy.