Heats of vaporization, Delta H-V, of the monomers HF and H2O from 50 mol % aqueous HF were determined to 150 degrees C (HF to 300 degrees C) under saturation pressures using Inconel and Monel cells with sapphire windows. Heats were obtained from the temperature dependences of the integrated Raman intensities, as well as the peak heights, of the 3958 and 3652 cm(-1) vapor bands from HF and H2O, respectively, ratioed against the 2329 cm(-1) band from the N-2 internal standard. The Raman Delta H-V for the HF at 20 degrees C, 9340 +/- 220 cal/mol, agrees well with 20 degrees C calorimetric data, but it decreases to 6600 +/- 200 cal/mol at 150 degrees C. The Raman Delta H-V, values for H2O are larger by the approximate to Delta H of one H-bond; they are 11 800 +/- 300 and 9350 +/- 350 cal/mol at 25 and 150 degrees C, respectively. The H-bonded dimer, (HF)(2), contributes relatively little to the gas-phase spectrum below approximate to 150 degrees C, but its Raman intensity, centered near 3931 cm(-1), rises rapidly between 150 and 300 degrees C. (HF)(2) vaporizes first, but its H-bond breaks almost instantaneously in the vapor to give the monomer, except that the dimer finally becomes more favorable at very high saturation pressures. Gaussian deconvolution of the broad, structured, nominal 3600 cm(-1) contour from the liquid between -12 and approximate to 150 degrees C yielded an H-bond enthalpy of 2.8 +/- 0.2 kcal/mol OH ... F, which falls within the range of 2.5(-0.1)(+0.6) kcal/mol OH ... F obtained from Young-Westerdahl analysis involving -Delta H-INT = g(B) = Delta H-V(Raman)(HF,Solution) + Delta H-V(Raman) (H2O,solution) - Delta H-V(HF,pure liquid) - Delta H-V(H2O,pure liquid). The 50 moi % solution is essentially a molten salt composed of very strong H2OH+... F- complexes interbonded via peripheral H-bonds having ordinary, approximate to 2.9 Angstrom, O-F distances. The Delta H of 2.5-2.8 kcal/mol refers to breakage of such peripheral H-bonds, and this breakage produces a pronounced Raman intensity increase near 3590 cm(-1) due to dangling, non-H-bonded proton(s), schematically the left protons of H2OH+, or to the (above right of) F-. Three valence vibrations due to the O-H stretches of the H3O+ ion were observed. However, a fourth, very broad, valence vibration from the H+... F- stretching of the H2OH+ F- complex was also observed, near 2900-3000 cm(-1) which results from proton transfer in a double-well potential with a very short, approximate to 2.4 Angstrom, O-F distance. A detailed energy analysis of the complete vaporization process also suggests that the hydronium-fluoride H-bond, between the H2OH+ and the F- (above), has an unusually large energy, estimated to be at least approximate to 8 kcal/mol, thus breaking only upon vaporization, or at temperatures above those employed here for solution studies.