Am
Americium
Z 95 243.0 g/molActinide Radioactive
Nucleus
95 Protons
148 Neutrons
95 Electrons (2 Valence)
Shell distribution: K2 • L8 • M18 • N32 • O25 • P8 • Q2
Electron Configuration
Energy
7p
6d
5f
7s
6p
5d
4f
6s
5p
4d
5s
4p
3d
4s
3p
3s
2p
2s
1s
[Rn]5f77s2
Oxidation States
CommonRare
0
Pick a state to see its ions
Radii
Empirical
175 pm1.75 Å
Calculated
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Covalent
180±6 pm1.8±0.06 Å
Van der Waals
244 pm2.44 Å
IonicAm3+
97.5 pm0.975 Å
Crystal Structure
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Double hexagonal close-packedStandard state
Pearson symbol
hP4
Space group
P63/mmc No. 194
Density
12 g/cm³