DIODE-LASER APPLICATION FOR RESEARCH OF MOLECULAR-IONS

We have developed several methods of diode laser spectroscopy and have applied them for high-resolution spectroscopy and kinetic studies of molecular ions. For these purposes we have used a special high-voltage modulation technique for generation of ions in the plasma of a gas discharge. This modulator enables the studies of the formation and decay processes of ions. The modulator can also alternately switch the polarity of a high voltage and can be used for experimental measurement of velocity modulation of ions in the gas discharge. It was found that this spectrometer can be successfully used in the following regions: velocity modulation spectroscopy of molecular ions (ArD+, SD-), distinction between the velocity modulation signal of cation and anion (due to the reverse phase of both signals), measurement of Doppler shifts of ions (information about the velocity and mobilities of ions), ion kinetics (measurement of times of formation and decay of ions in the gas discharge).