Molecular recognition involving small gas-phase molecules

2 How to determine the angular geometry and strength of intermolecular binding for an isolated dimer 

The important conclusion that the equilibrium geometry of HjO - HF is pyramidal (not planar) at oxygen was thereby established. For the related molecule (CH2)20 -HF, an examination of the appropriate vibrational satellites established that this dimer too is pyramidal, with a higher and wider 

The other measure of strength of binding, D, can be obtained by measuring the absolute intensity of a rotational transition of H2O HF and of H2O in an equilibrium gas mixture of H2O, HF and H20---HF. The intensity leads to the number density o,o(B) of the component B in its p = 0, J = 0 state and thence to Dq from the relation 

If sufficient is known of the contribution of the various vibrational modes of H20 - HF to the zero-point energy, o can be corrected to give D. The experimentally determined values are = 34.3(3)kJmol and = 42.9(8) kJmol i [7]. 

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Legon AC, Millen DJ (1993) Molecular recognition involving small gas-phase molecules. In Buckingham AD, Legon AC, Roberts SM (eds) Principles of molecular recognition. Blackie, London, pl7... 

Molecular recognition involving small gas-phase molecules... 

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