Binary Complexes of Hydrogen Fluoride and Water

Let us now turn to three examples of hydrogen-bonded complexes wich are known best at present (HF)2, H20 HF and (HjO) In Fig. 5 their equilibrium structures, 

Anton Beyer, Alfred Karpfen and Peter Schuster 

The complex H20 HF is the most stable aggregate the calculated energy of interaction is AE = —7.5 kcal/mol. The two homodimers are of comparable stability (HF)2, AE = —3.8 kcal/mol, and (H20)2, AE = —4.0 kcal/mol. The fourth combination HF HOH represents the least stable structure AE = —1.9 kcal/mol. It has therefore not been observed so far in mixtures of HF and HjO vapor. 

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