Determination of properties of hydrogen-bonded dimers by rotational spectroscopy and a classfication of dimer geometries

摘要: Rotational spectroscopy is a rich source of information about the molecular geometry, potential-energy function and electric-charge distribution simple hydrogen-bonded dimers in gas phase. Techniques for observation such spectra are now available have led to considerable amount wide range dimers. We outline two techniques that been used then review various properties can be derived from observed spectroscopic constants. indicate how vibrational ground-state rotational centrifugal distortion constants lead geometry observations Stark effect nuclear quadrupole hyperfine structure allow conclusions charge redistribution on dimer formation. also show important obtained by study vibrationally excited states. Two specific examples, HCN ⋯ HF N2⋯ HF, examined detail before general discussion results number species presented which geometries, force dissociation energies compared systematically. that, although geometries correspond broad potential energy minima, it nevertheless possible propose rule accounts preferred equilibrium conformation.