The liquid-state structure of octafluoropropane and decafluoro-n-butane asdetermined by neutron diffraction

The liquid-state structures of octafluoropropane (perfluoropropane, R218) a nd decafluoro-n-butane (perfluorobutane) have been determined at 150 K, 250 K and 299 K using neutron scattering techniques: Analysis of the results h as shown that there is no observable difference between the intramolecular structure of octafluoropropane observed in this work and that determined by electron diffraction. Noticeable intermolecular structure has been observe d including a distinct peak at 0.320 nm that must be due to a close intermo lecular F...F separation. Interpretation of the structure of decafluoro-n-b utane has been hampered by the existence of more than one conformation at e quilibrium. The close, intermolecular, F...F separation is clearly visible.