title: Interactions between freons: a rotational study of CH₂F₂-CH₂Cl₂.
abstract: The rotational spectra of two isotopologues of a 1:1 difluoromethane-dichloromethane complex have been investigated by pulsed-jet Fourier-transform microwave spectroscopy. The assigned (most stable) isomer has C(s) symmetry and it displays a network of two C-H⋅⋅⋅Cl-C and one C-H⋅⋅⋅F-C weak hydrogen bonds, thus suggesting that the former interactions are stronger. The hyperfine structures owing to (35)Cl (or (37)Cl) quadrupolar effects have been fully resolved, thus leading to an accurate determination of the three diagonal (χ(gg); g=a, b, c) and the three mixed quadrupole coupling constants (χ(gg'); g, g'=a, b, c; g≠g'). Information on the structural parameters of the hydrogen bonds has been obtained. The dissociation energy of the complex has been estimated to be 7.6 kJ mol(-1).
authors.affiliation: Dipartimento di Chimica "G. Ciamician", Università di Bologna, Via Selmi 2, I-40126 Bologna (Italy), Fax: (+39) 0512099456.
authors.forename: Qian
authors.initials: Q
authors.lastname: Gou
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Spada
authors.forename: Montserrat
authors.initials: M
authors.lastname: Vallejo-López
authors.forename: Zbigniew
authors.initials: Z
authors.lastname: Kisiel
authors.forename: Walther
authors.initials: W
authors.lastname: Caminati
keywords: fluorine; freons; hydrogen bonds; non-bonding interactions; rotational spectroscopy