  The use of radioactive molecules for fundamental physics research is a
developing interdisciplinary field limited dominantly by their scarce
availability. In this work, radioactive molecular ion beams containing actinide
nuclei extracted from uranium carbide targets are produced via the Isotope
Separation On-Line technique at the CERN-ISOLDE facility. Two methods of
molecular beam production are studied: extraction of molecular ion beams from
the ion source, and formation of molecular ions from the mass-separated ion
beam in a gas-filled radio-frequency quadrupole ion trap. Ion currents of
U$^+$, UO$_{1-3}^+$, UC$_{1-3}^+$, UF$_{1-4}^+$, UF$_{1,2}$O$_{1,2}^+$ are
reported. Metastable tantalum and uranium fluoride molecular ions are
identified. Formation of UO$_{1-3}^+$, U(OH)$_{1-3}^+$, UC$_{1-3}^+$,
UF$_{1,2}$O$_{1,2}^+$ from mass-separated beams of U$^+$, UF$_{1,2}^+$ with
residual gas is observed in the ion trap. The effect of trapping time on
molecular formation is presented.
