Short-lived radioisotopes of molybdenum, technetium and ruthenium as homologous elements of the superheavy elements seaborgium, bohrium and hassium can be produced in a 252Cf fission source. We have used this fission source to form very volatile metal carbonyls of Mo, Tc, Ru, Rh. One should, however, be aware that in the fission process many isotopes of an isobar are formed. Table 1 summarizes calculated independant yields in SF of 252Cf[1]. We have used this fission source to form very volatile metal carbonyls of Mo, Tc, Ru, Rh. One should, however, be aware that in the fission process many isotopes of an isobar are formed. Table 1 summarizes calculated independant yields in SF of 252Cf [1].