Neodymium vs Thulium

PropertyNd NeodymiumTm Thulium
Atomic number6069
SymbolNdTm
NameNeodymiumThulium
Categorylanthanidelanthanide
Standard Atomic Weight144.242 u168.93422 u
Period66
GroupN/AN/A
Blockss
Phase at STPsolidsolid
Electron configuration[Xe]6s24f4[Xe]6s24f13
Oxidation states[0, 2, 3, 4][0, 1, 2, 3]
Electronegativity (Pauling)1.141.25
Electron affinity1.913 eV1.029 eV
Density7010 kg/m³9320 kg/m³
Melting point1020.85 °C1544.85 °C
Boiling point3073.85 °C1949.85 °C
Discovery year18411879