Threshold behavior in electron-transfer collisions between rubidium atoms and C2F5Cl or C2F5I molecules.
Rubidium atoms are accelerated in a high-temperature expansion of hydrogen to produce beams with energies high enough to observe collisional ionization with a cross beam. The speed of the atoms is directly measured by time-of-flight techniques, and the positive and negative ions produced are detected in separate mass spectrometers and detected in coincidence. Chloroperfluoroethane produces C(2)F(5)(-) and Cl(-) ions, whereas iodoperfluoroethane produces I(-), C(2)F(5)(-), and C(2)F(5)I(-) ions. When the measured speed distributions are used, the signal versus energy may be deconvolved to yield thresholds and electron affinities (EAs). The EA for C(2)F(5)I is measured to be 0.96 +/- 0.1 eV. Anomalously high EA values result for C(2)F(5) apparently because C(2)F(5)(-) is produced by parts per million concentrations of Rb(2).
Jia
Beike
B
Chemistry Department and Rice Quantum Institute, Rice University, Houston, TX 77251, USA.
Harris
Sean
S
Lewis
Larry L
LL
Zhan
Jiping
J
Brooks
Philip R
PR
D004579:Electron Transport; D013058:Mass Spectrometry; D012413:Rubidium / Q000737:chemistry*
D012413:Rubidium