The vibrational spectra of UBz and ThBz have been measured in solid argon. Complementary quantum chemical calculations have allowed the assignments of the vibrational spectra. According to the calculations, AcBz are stable molecules, as well as other species like BzAcBz and BzAc(2)Bz. Experimentally, there is no evidence for the sandwich compounds BzAcBz and BzAc(2)Bz due to the limitations in the reagent concentrations.