Terbium vs Thallium

PropertyTb TerbiumTl Thallium
Atomic number6581
SymbolTbTl
NameTerbiumThallium
Categorylanthanidepost-transition-metal
Standard Atomic Weight158.92535 u204.3835 u
Period66
GroupN/A13
Blocksp
Phase at STPsolidsolid
Electron configuration[Xe]6s24f9[Xe]6s24f145d106p1
Oxidation states[0, 1, 2, 3, 4][-5, -2, -1, 1, 2, 3]
Electronegativity (Pauling)N/A1.62
Electron affinity1.124 eV0.377 eV
Density8230 kg/m³1.180000e+4 kg/m³
Melting point1355.85 °C303.85 °C
Boiling point3229.85 °C1472.85 °C
Discovery year18431861