High-resolution rotational spectroscopy of NNOH+, DCS+, Ar⋯D3+, Ar ⋯ DCO+, and Ar⋯HN2+

The rotational spectra of the protonated molecules NNOH+ and DCS+, and the ion complexes Ar⋯D3+, Ar ⋯ DCO+, and Ar ⋯ HNN+ have been detected by Fourier transform microwave spectroscopy at high spectral resolution, in which the supersonic molecular beam expands along the axis of the Farby-Perot cavity. These new measurements either better resolve or reveal additional line structure not observed in the previous lower resolution studies. Precise nitrogen or deuterium quadrupole coupling constants have been determined for the first time for both ions and Ar ⋯ DCO+; a tunneling splitting of 72±5kHz has been measured for the 10,1→00,0 transition of Ar⋯D3+.