Thulium, Tm

Thulium is a chemical element that has the symbol Tm and atomic number 69. A lanthanide element, thulium is the least abundant of the rare earths. It is an easily workable metal with a bright silvery-gray luster and can be cut by a knife. It has some corrosion resistance in dry air and good ductility. Naturally occurring thulium is made entirely of the stable isotope Tm-169.

Technical Data
Symbol Tm Density (25°C)/gcm3 9.318
Atomic number 69 Melting point /°C 1545
No. of naturally occurring isotopes 1 Boiling point /°C -1727
Atomic weight 168.9342 ΔHvap/kJmol-1 247
Outer electron configuration 4f136s2 ΔHf(monoatomic gas)/kJmol-1 232
Metal radius(6-coordinate)/pm 175.9 ΔH(hydration Ln3+)/kJmol-1 3717
Ionic radius(6-coordinate)/pm III 88 Ionization energy/kJmol-1 I 589
Ionic radius(6-coordinate)/pm II 103 Ionization energy/kJmol-1 II 1163
E° (M3+(aq)\ + 3e- →M(s))/V -2.278 Ionization energy/kJmol-1 III 2305
Electrical resistivity (25°C)/μohm cm 90    
Evaporation Techniques
Temperature (oC) @Vap. Pressure Techniques Remarks
10-8 Torr 10-6 Torr 10-4 Torr Electron Beam Crucible Coil Boat
461 Sublimes 554 Sublimes 680 Sublimes Good Al2O3 - Tantalum  

Evaporation Materials
T6-5000-M pieces 12mm and smaller

The foils are available in either rectangular or circular shape. Please enter width and length or diameter of the required foil.

Foil
T6-3003-F 0.004" (0.1mm)
T6-3007-F 0.008" (0.2mm)
Powder
T6-10000-P -40 mesh
Rods
T6-2000-R 0.250" (6.35mm)
T6-2001-R 0.500" (12.7mm)
Sheet
T6-4001-S 0.015" (0.38mm)
T6-4002-S 0.020" (0.5mm)
T6-4003-S 0.030" (0.76mm)
T6-4004-S 0.040" (1mm)