Show Elements
ID 27
Symbol Tm
Name Thulium
Density (g/cm<sup>3</sup>) 9.32
Atomic Number 69
Molecular Weight 169
Melting Point (K) 1818
Boiling Point (K) 2223
Specific Heat Capacity (J/kg K) 160
Electro Negativity 1.25
Curie temperature (K)
Bohr Magneton (J/T)
Magnetization Saturation (MA m<sup>-1</sup>)
Crystal Structure ​Hexagonal close-packed (hcp)
Appearance Silvery gray
Element category Lanthanide
Magnetic ordering Paramagnetic 
Discovery Per Teodor Cleve (1879)
General Information Thulium emits blue light upon excitation, a property that is exploited in flat panel display screens. Thulium also has useful applications in low-levelradiation detection and other luminescence applications, such as halide discharge lamps.
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