Periodic Table/Neptunium/²²¹Np

← 220Np222Np →

²²¹Np

Neptunium-221

Radioactive

Nuclear Propertiesbinding energy · spin-parity · abundance

Protons (Z)

93

Neutrons (N)

128

Mass Number (A)

221

Atomic Mass

221.032110AMU

Spin / Parity

9/2-

Binding E/A

7.392keV

Natural Abundance

Trace / None

Half-life

Unknown

Decay Modesoverview · half-life · α · β⁻ · β⁺

α

Decay Chain

²²¹NpNeptunium?

α

²¹⁷PaProtactinium3.80 ms

α100.0%

β⁻²¹⁷U

²¹³AcActinium738 ms

α100.0%

β⁺²¹³Ra

²⁰⁹FrFrancium50.5 s

α89.0%

β⁺²⁰⁹Rn11.0%

²⁰⁵AtAstatine26.9 min

β⁺90.0%

α²⁰¹Bi10.0%

²⁰⁵PoPolonium1.74 h

β⁺100.0%

α²⁰¹Pb0.04%

²⁰⁵BiBismuth14.9 d

β⁺100.0%

²⁰⁵PbLead17.0 My

EC100.0%

²⁰⁵TlThalliumSTABLE

9-step decay chain → stable · Primary path shown · branching ratios indicated

Other Isotopes of Neptunium

219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245

← Back to NeptuniumData: IAEA NDS · ENSDF