Dynamics of hydrogen-HF complexes in helium nanodroplets

High-resolution infrared spectra are reported for ortho- and para-H-2, ortho- and para-D-2, and HD binary complexes with HF, solvated in helium nanodroplets. These rotationally resolved spectra provide detailed information on the rotational and vibrational dynamics of these systems. The para-H-2-HF complex is observed, indicative of the unusual growth conditions present in the droplets. In the case of the HD-HF complex, extensive line broadening is observed, which we tentatively explain in terms of the near resonance between the HF and HD vibrational frequencies, which presumably facilitates vibrational relaxation. (C) 2003 American Institute of Physics.