ISSN:
1089-7623
Source:
AIP Digital Archive
Topics:
Physics
,
Electrical Engineering, Measurement and Control Technology
Notes:
A selected ion flow tube apparatus is coupled with laser induced fluorescence (LIF) detection for the selective monitoring of ion vibrational states and their reactions. Mass selected ions are injected into a flow tube with a venturi inlet using He carrier gas. A 200 Hz dye laser system provides sensitive LIF detection of the injected ions at densities as low as 1×105 cm−3 for N+2. The rotational temperatures of the N+2 ions are estimated to be ≈300 K using the LIF detection, while the vibrational temperatures can be high and may be varied by the injection potentials. Vibrationally state-selected ion-molecule reactions of N+2(v=0, 1, and 2) are studied with N2, Ar, and O2 at thermal kinetic energies (Elab〈0.1 eV), where translation-to-vibration energy transfer is negligible. Isotopically specific charge-transfer reactions of 15N+2(v) with 14N2 are also studied. The ability to mass select ions and characterize their vibrational states and those of their reaction products allows novel studies of state-to-state ion chemistry.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.1144367
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