To investigate the interactions of Fe-57 atoms with sulfur hexafluoride SF6 molecules, in-beam Mossbauer spectra were measured for Mn-57 implanted SF6 at 9 K and 65 K. Isolated Fe-57 atoms or ions produced by beta-decay were not trapped within the SF6 matrix. At 9 K, monomeric FeF2 and FeF3 molecules were produced by reaction of Fe-57 with F atoms released by decomposition of the SF6 molecules. When the temperature of the SF6 solid was increased to 65 K, FeF4 was formed in addition to FeF2 and FeF3. Density functional calculations were performed to confirm the assignments of the candidate species identified in the Mossbauer spectra.