H Home Background Color: He Li Be Neptunium Main Page Black White Gray B C N O F Ne Na Mg Neptunium Pictures Page Al Si P S Cl Ar K Ca Neptunium Technical Data Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr Rb Sr Y Zr Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb Te I Xe Cs Ba La Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu Hf Ta W Re Os Ir Pt Au Hg Tl Pb Bi Po At Rn Fr Ra Ac Th Pa U Np Pu Am Cm Bk Cf Es Fm Md No Lr Rf Db Sg Bh Hs Mt Ds Rg Cn Nh Fl Mc Lv Ts Og

Isotopes of Neptunium (click to see decay chain): 225Np  226Np  227Np  228Np  229Np  230Np  231Np  232Np  233Np  234Np  235Np  236Np  237Np  238Np  239Np  240Np  241Np  242Np  243Np  244Np

231Np     Half-life Boson, 93p 138n 48.83333333333 m Spin 5/2 Parity 1 Show Decay Modes Hide Ultimate Decay Products Yield Nuclide 100.2802389509% 207Pb 8.75056188×10-8% 205Tl 9.702×10-13% 208Pb Atomic Weight 231.038245085 Abundance None Mass Excess 35.625068MeV Binding Energy 7.602125MeV Magnetic Moment N/A Quadrupole Moment N/A   Show Element Pictures. Also show decay chains leading to this isotope. Show only decays with probability >0.1%. Show Decay Image Smaller.

Click any isotope in diagram to see its data. Decay chain image generated by Mathematica's GraphPlot and IsotopeData functions from Wolfram Research, Inc..