Velocity modulation laser spectroscopy of molecular ions

Abstract

34 v = 1 ← 0 R branch infrared transitions in the X ²Π state of the HF⁺ molecular ion have been measured by velocity modulation laser absorption spectroscopy. Fluorine hyperfine structure was resolved for low J transitions. From a weighted fit of all available high resolution data, values were determined for the v = 0 and v = 1 fluorine hyperfine constants (except b(1)), λ-doubling parameters, rotational and centrifugal distortion constants and the vibrational band origin. Molecular expectation values derived from the hyperfine constants are compared to similar quantities for OH and NH^-. An analysis is presented for the v = 0 proton hyperfine structure observed previously by laser magnetic resonance.