Vibrational spectra of hydrogen-bonded complexes on zeolite surfaces as a benchmark for evaluating performance of ab initio methods. Complex with the pyridinium ion

Ab initio molecular orbital theory has been used to compute the properties of a number of hydrogen-bonded complexes between fluoroacetylene as proton donor and ammonia, water, hydrogen fluoride, phosphine, hydrogen sulfide, and hydrogen chloride as proton acceptors. The properties considered were the vibrational spectra, the molecular structures, the hydrogen-bond energies, and the electron densities, and one of the aims of the study was to ascertain whether there was any evidence of blue-shifting hydrogen-bond character in the complexes formed. The adducts with NH3, H2O, PH3, and H2S were of the conventional CH···X kind (X = N, O, P, S), with hydrogen-bond energies decreasing in the order NH3 > H2O > PH3 ≈ H2S. Those formed with HF and HCl showed the presence of three alternative structures; in addition to the CH···F(Cl) complexes, adducts of the F(Cl)H···F and F(Cl)H···π type were also found to be stationary points on the potential energy surfaces, with stabilities in the order F(Cl)H···π > CH···F(Cl) > F(Cl)H···F. The hydrogen-bond energies of the CH···X series correlated with the gas-phase basicities of the proton acceptors; moreover, the CH bond-length changes, the wavenumber shifts, the complex–monomer infrared intensity ratios of the CH stretching modes, and the amounts of charge transferred on complex formation were all found to track with the hydrogen-bond energies. All those properties considered here are consistent with the formation of red-shifting hydrogen bonds, to the exclusion of the blue-shifting alternatives.

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An ab initio SCF-MO study of the hydrogen-bonded complexes formed between cyanoacetylene HCCCN and HF/HCl/HBr

Journal of Molecular Structure THEOCHEM ◽

10.1016/0166-1280(86)80041-0 ◽

1986 ◽

Vol 135 ◽

pp. 1-6 ◽

Cited By ~ 3

Author(s):

Alan Hinchliffe

Keyword(s):

Ab Initio ◽

Bonded Complexes ◽

Hydrogen Bonded

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A test of ab initio-generated, radial intermolecular potential energy functions for five axially-symmetric, hydrogen-bonded complexes B⋯HF, where B = N2, CO, PH3, HCN and NH3

Physical Chemistry Chemical Physics ◽

10.1039/d1cp00045d ◽

2021 ◽

Vol 23 (12) ◽

pp. 7271-7279

Author(s):

Anthony C. Legon

Keyword(s):

Hydrogen Bond ◽

Potential Energy ◽

Ab Initio ◽

Intermolecular Potential ◽

Axially Symmetric ◽

Energy Functions ◽

Potential Energy Functions ◽

Acceptor Atom ◽

Bonded Complexes ◽

Hydrogen Bonded

Radial P.E. functions of hydrogen-bonded complexes B⋯HF (B = N2, CO, PH3, HCN and NH3) have been calculated ab initio at the CCSD(T)(F12C)/cc-pVTZ-F12 level as a function of the hydrogen-bond length r(Z⋯H), where Z is the H-bond acceptor atom of B.

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