I2-catalyzed isomerizations of 3-fluoropropene and 3, 3-difluoropropene, and a Cope rearrangement of 1, 1-difluoro-1, 5-hexadiene provide thermodynamic data which allow the determination of a number of important group values for contributions to ΔHof which when combined with those determined in the preceding paper allow the calculations of ΔHof's of most simple F-substituted hydrocarbons:[Cd(F)(H)]=− 38.4,[Cd(F) 2]=− 88.0,[C(F) 2 (C ...