We report experimental studies of the formation of CF3O- by ion-molecule and electron attachment reactions, and theoretical investigations of the structure and energetics of CF3O- and its neutral counterpart CF3O. The anion CF3O- is formed from the rapid attachment of free electrons to its neutral dimer, (CF3O)(2). Potential sources of CF3O- through ion-molecule reactions of CF3- and F- were surveyed. CF3O- is formed in the bimolecular ion-molecule reaction of CF3- with SO2 and the third-order association reaction of F- with CF2O. In addition, rate constants for the reactions of CF3- with a variety of neutral compounds were measured. A number of cases were found in which formation of CF3O- was energetically allowed but was not observed. The potential energy surfaces of CF3O and CF3O-have been investigated using a variety of density functional theory (DFT) techniques. The ground-state minimum energy structure of CF3O was found to be a (2)A' Jahn-Teller distorted C-s-symmetry structure, while for the anion the ground state is (1)A(1) with a C-3v-symmetry minimum. A search for other low-energy minima for CF3O- was unsuccessful. The DFT methods support a value for the adiabatic electron affinity of CF3O near 4.1 eV.