The potential of strained fluorocarbons, which can act as oxidizers in metal-based pyrolant systems, is investigated. The oxidizing performance of fluorocarbons is evaluated by the enthalpy of combustion Delta(c)H(298K) and the fractional electron transfer DeltaN. Delta(c)H(298K) can be related to hybridisation, molar C/F ratio and strain of the parent carbon skeleton of the fluorocarbon. Considered fluorocarbons are tetrafluorotetrahedrane (CF)(4) (3), tetrakis(trifluoromethyl)tetrahedrane C-4(CF3)(4) (4), hexafluoro[3]prismane (CF)(6) (5), hexakis(trifluoromethyl)[3]prismane C-6(CF3)(6) (6), octafluorocubane (CF)(8) (7), octakis(trifluoromethyl)cubane C-8(CF3)(8) (8), eicosafluorododecahedrane (CF)(20) (9), eicosakis(trifluoromethyl)dodecahedrane C-20(CF3)(20) (10), C60F48 (11) and perfluorofullerane (CF)(60) (12). Powerful oxidisers in terms of exothermicity are those possessing both tertiary C-F-units and strained carbon skeletons. Nevertheless the reactivity, which is estimated on basis of DeltaN, the fraction of electrons transferred according to Pearson, has been found to be high with the corresponding perfluoromethyl derivatives and maximum with the fluorofulleranes. For part IV see Ref. 17.