Energy relaxation dynamics of photofragments produced from photodissociation of trifluoromethyl iodide (CF3I) in argon at 266 nm was studied by means of a time-resolved probe beam deflection (PBD) technique. It was found that the PBD transients observed in Ar environment consist of two heat-releasing (via collisional relaxation) processes that can be assigned to translational-to-translational (T-T) and vibrational-to-translational (V-T) energy transfers of photofragments. From the relaxation times and the fractions of the two processes, 15% of the excess energy from photodissociation was found to be partitioned into vibrational modes of CS radicals while the remaining 85% goes to translation. In addition, the intermolecular V-T energy-transfer rate constant between CF3 and Ar was determined to be similar to 8.0 x 10(2) s(-1) Torr(-1). Electronic to translational (E-T) energy transfer from the spin-orbit excited iodine fragment, I*(P-2(1/2)), to the medium was not observed in the time domain employed in this study, unless oxygen, a well-known I* quencher, was added to facilitate the transfer process. An excellent agreement between the obtained results and previously reported photofragment translational spectroscopy results indicates that the energy relaxation processes of photofragments as well as energy partitioning of excess energy can be studied by the PBD method presented in this study.