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The structure of fluid trifluoromethane and methylfluoride

J. Neuefeind·H. E. Fischer·W. Schröer
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Abstract

We present hard X-ray and neutron diffraction measurements on the polar fluorocarbons HCF3 and H3CF under supercritical conditions and for a range of molecular densities spanning about a factor of ten. The Levesque-Weiss-Reatto inversion scheme has been used to deduce the site-site potentials underlying the measured partial pair distribution functions. The orientational correlations between adjacent fluorocarbon molecules -- which are characterized by quite large dipole moments but no tendency to form hydrogen bonds -- are small compared to a highly polar system like fluid hydrogen chloride. In fact, the orientational correlations in HCF3 and H3CF are found to be nearly as small as those of fluid CF4, a fluorocarbon with no dipole moment.

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J. Neuefeind, H. E. Fischer, W. Schröer. 2000-06-09. The structure of fluid trifluoromethane and methylfluoride. https://doi.org/10.1088/0953-8984%2F12%2F41%2F302

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