We present a detailed study of the lanthanide(III) complexes with cyclen-based ligands containing phenylacetamide pendants that incorporate CF3 group(s) at different distances from the metal ion. The complexes exhibit square-antiprismatic coordination in solution, as demonstrated by analysis of the Yb3+-induced paramagnetic shifts and the X-ray structure of the [YbL3] complex. Luminescence lifetime measurements and a detailed H-1 and O-17 relaxometric characterization confirmed the presence of an inner-sphere H2O molecule. The Tm3+ complexes provide chemical-exchange saturation-transfer response upon saturation at the frequency of the amide protons. A F-19 relaxation study provided accurate estimates of the Ln center dot center dot center dot F distances that were used to rationalize the efficiency of the complexes as F-19 magnetic resonance imaging (MRI) probes, which was tested in vitro using MRI phantom studies.