New apparatus for the study of ion-molecule reactions at very high pressure (25-700 Torr): A turbulent ion flow tube (TIFT) study of the reaction of SF6-+SO2

A new instrument, the turbulent ion flow tube (TIFT), has been developed fo r studying ion-molecule reactions up to atmospheric pressure. The instrumen t is based on the turbulent flow neutral reactor developed by Seeley ee al. ,(8) and it operates under turbulent rather than laminar flow conditions. T he TIFT is currently designed to operate at room temperature over a pressur e range from approximately 20-750 Torr, although higher pressures are possi ble with minor modifications. In this initial report, 300 K rate constants and product distributions, measured from 25 to 700 Torr, are presented for the reaction of SF6- with SO2. Both the rate constants and product distribu tions for this reaction are independent of pressure, and the present result s are consistent with previous measurements made at <1 Torr.