Weak hydrogen bonds in adducts between freons: the rotational study of CH2F2–CH2ClF

Abstract

The rotational spectra of 2 isotopologues of the molecular adduct CH₂F₂–CH₂ClF show that the two subunits are held together through two weak C–H⋯F–C and one C–H⋯Cl–C linkages, rather than through three weak C–H⋯F–C connections. This suggests the weak Cl⋯H interaction to be observed preferentially to a weak F⋯H one. Structural information on these weak hydrogen bonds has been obtained. The dissociation energy has been estimated from centrifugal distortion to be 5.3 kJ mol⁻¹.