Some ion chemistry of HC5N

The ion–molecule chemistry of 2,4-pentadiynenitrile, HC5N, a cyanopolyyne, has been investigated in a flowing afterglow-selected ion flow tube (FA-SIFT) operating at room temperature. The ion chemistry of a selection of ions of relevance to the interstellar and Titan environments was examined. The proton affinity of HC5N was found from both measurement and calculation to be 770 ± 20 kJ mol−1. Rapid proton transfer was observed to occur for many of the ions known to be present in Titan's ionosphere.