A New Isotope,Pt201

A new Pt isotope was found by irradiation of mercury compounds with neutrons in the PRNC nuclear reactor. The Pt activities were separated from the mixture by precipitations as the ${\mathrm{K}}_2$Pt${\mathrm{Cl}}_6$. In this fraction, a 2.3±0.2 min activity could be attributed to ${\mathrm{Pt}}^{201}$, produced by ${\mathrm{Hg}}^{204}(n, \alpha ){\mathrm{Pt}}^{201}$. The ${\mathrm{Pt}}^{201}$ decays to the well-known ${\mathrm{Au}}^{201}$. The genetic relationship was established by chemical separations of the daughter nuclide. The ${\mathrm{Au}}^{201}$ was identified by its half-life and its gamma-ray energy. Further, the growth of the gamma ray of 0.55 MeV, corresponding to ${\mathrm{Au}}^{201}$, was measured in the isolated Pt fraction, with a 4-in.×4-in. NaI(Tl) scintillator coupled to a 512-channel pulse-height analyzer. The values of Butement and Shillito for ${\mathrm{Au}}^{201}$ were confirmed.