Rotational spectrum and dynamics of tetrahydrofuran-argon

The jet-cooled rotational spectrum of the tetrahydrofuran-argon molecular c omplex has been investigated by millimeterwave absorption and Fourier trans form microwave spectroscopies. The argon atom is located nearly over the ox ygen atom, almost perpendicularly to the COC plane. Each rotational transit ion is split in two component lines due to the residual pseudorotational ef fects of the ring in the complex. The splitting between the two vibrational sublevels has been calculated to be 111.345(44) MHz. (C) 1998 Elsevier Sci ence B.V. All rights reserved.