Protonated Hypofluorous Acid

Geometrical parameters (r in A) from the SCF-MO calculations for H20F and for trans-HOFH (for the somewhat less stable cis-HOFH , see original paper) [2] follow  

HO2F is assumed to be an intermediate in the reaction of F2 with H2O2 in aqueous solution 

The standard enthalpy of formation AH = -8.7 kcal/mol was derived from a calculated value of 6.3 kcal/mol for the enthalpy of the (hypothetical) reaction H02F(g)-i-H20(g)- H202(g) + HOF(g). This reaction enthalpy was derived from SCF total energies of the reactants and products [3] and is called a bond separation energy , since a molecule with three heavy atoms (HO2F) is converted into molecules with two heavy atoms and the same type of formal bonds [1, 2, 3]. For AH (H0F), an estimated value of -27.7 kcal/mol was inserted, cf. p. 137, [3]. AHf°(H02F) =-25.6 kcal/mol (-107.12 kJ/mol) was calculated by a semiempirical SCF-MO method (MINDO) [4]. 

The dipole moment fx = 2.64 D (presumably for the standard geometry from [3]) and the ionization potential Ej=14.75eV were calculated in [5] for atomic charges, see the original paper. 

A dihedral angle 0 = 75° follows from an ab initio calculation [7], in which the residual structural parameters had their standard values. 

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