The equilibrium conformation, dynamics, and dissociation energy of the weakly bonded dimethylether...Ne complex have been deduced from its pulsed jet millimeter wave spectrum. Each rotational transition is split into two component lines. The corresponding vibrational splitting has been determined to be DeltaE=807.2(9) MHz. The inversion barrier between the two equivalent minima with Ne above or below the COC plane has been calculated from this datum to be 16 cm(-1). The dissociation energy of the complex is estimated, from the centrifugal distortion constant D-J, to be ca. 1.0 kJ/mol. (C) 2003 American Institute of Physics.