High precision measurements of carbon disulfide negative ion mobility and diffusion.

High precision measurements were made of reduced mobility, lateral and longitudinal diffusion of CS2− ions in 40 Torr CS2 and a 30–10 Torr CS2–CF4 gas mixture. The reduced mobility was found to be 0.4645 ± 0.0006 cm2 atm/s V in CS2 and 0.523 ± 0.001 cm2 atm/s V in the CS2–CF4 gas mixture at STP. The lateral diffusion temperatures for these two gases (295 ± 15 K and 297 ± 6 K) were found to be in good agreement with room temperature. By contrast longitudinal diffusion temperature was found to be slightly elevated (319 ± 10 (stat) ± 8 (sys) K and 310 ± 20 (stat) ± 6 (sys) K) though given the errors, room temperature diffusion cannot be ruled out. For lateral diffusion, significant capture distances (0.21 ± 0.07 mm and 0.15 ± 0.03 mm) were measured while for longitudinal diffusion the results were not conclusive.