Browse/search for people

Publication - Professor Anthony Legon

    Nonbonding pairs in cyclic thioethers

    Electrostatic modeling and ab initio calculations for complexes of 2,5-dihydrothiophene, thietane, and thiirane with hydrogen fluoride

    Citation

    Hill, JG & Legon, AC, 2019, ‘Nonbonding pairs in cyclic thioethers: Electrostatic modeling and ab initio calculations for complexes of 2,5-dihydrothiophene, thietane, and thiirane with hydrogen fluoride’. International Journal of Quantum Chemistry, vol 119.

    Abstract


    Electrostatic potential energies V(ϕ) of a non-perturbing, protonic charge at fixed distances r from the S atom in three cyclic thioethers were examined as functions of the angles ϕ made by the r-vector with the C
    2
    axis (thiirane and 2,5-dihydrothiophene) or the local C
    2
    axis (thietane). The electrostatic PE V
    HF
    (ϕ) of HF (HF modelled as an extended electric dipole) was also calculated and the results compared with geometries of the thioether⋯HF complexes calculated at the CCSD(T)-F12c/cc-pVTZ-F12 level. The latter reveal angular deviations θ ∼10-20° of the S⋯HF nuclei from collinearity in directions suggesting secondary interactions of F with H atom(s) of the rings. Angles ϕ made by the S⋯H hydrogen bond with the C
    2
    (or local C
    2
    ) axes in the complexes are systematically larger (∼4-9°) than indicated by the V
    HF
    (ϕ) functions. Minima in the simple V(ϕ) versus ϕ functions occur at values smaller (∼5-10°) than those in the V
    HF
    (ϕ) curves.

    Full details in the University publications repository