Samarium vs Erbium

PropertySm SamariumEr Erbium
Atomic number6268
SymbolSmEr
NameSamariumErbium
Categorylanthanidelanthanide
Standard Atomic Weight150.36 u167.259 u
Period66
GroupN/AN/A
Blockss
Phase at STPsolidsolid
Electron configuration[Xe]6s24f6[Xe]6s24f12
Oxidation states[0, 1, 2, 3][0, 1, 2, 3]
Electronegativity (Pauling)1.171.24
Electron affinity0.156 eV0.312 eV
Density7520 kg/m³9070 kg/m³
Melting point1073.85 °C1528.85 °C
Boiling point1793.85 °C2867.85 °C
Discovery year18781843