Negative ion formation following low energy (0–10 eV) electron attachment to free and bound CF2Cl2 molecules is studied in (1) a molecular beam experiment (single molecules, homogeneous clusters, and mixed CF2Cl2/NH3 clusters) and (2) a UHV surface experiment where desorption of negative ions from condensed CF2Cl2 is observed. From single gas phase CF2Cl2 molecules we observe Cl− and F− generated via dissociative electron attachment from a resonance near 0 eV and 3 eV, respectively, as the most abundant ions. From homogeneous clusters (CF2Cl2)n, we additionally detect undissociated complexes of the form (M)n−(M=CF2Cl2) including the stabilized monomer CF2Cl2− and also “solvated fragment ions” of the form Mn⋅X−(X=Cl, F). Their relative abundance vs size (n) of the final product varies in a significant different way between (M)n− and Mn⋅X− reflecting the different relaxation probabilities in the initial cluster. In the desorption spectra, the dominant low energy Cl− gas phase resonance is strongly suppressed in favor of a significant resonant feature appearing near 8 eV. These last results are discussed in light of previously reported giant enhancements of electron induced desorption of Cl− and F− from CF2Cl2 on Ru coadsorbed with water or ammonia ices under 250 eV electron impact [Q. B. Lu and T. E. Madey, Phys. Rev. Lett. 82, 4122 (1999); J. Chem. Phys. 111, 2861 (1999)].