Ytterbium, Yb

Ytterbium is a chemical element with the symbol Yb and atomic number 70. A soft silvery metallic element, ytterbium is a rare earth of the lanthanide series and is found in the minerals gadolinite, monazite, and xenotime. The element is sometimes associated with yttrium or other related elements and is used in certain steels. Natural ytterbium is a mix of seven stable isotopes.

Ytterbium is a soft, malleable and rather ductile element that exhibits a bright silvery luster. A rare earth element, it is easily attacked and dissolved by mineral acids, slowly reacts with water, and oxidizes in air.

Ytterbium has three allotropes which are called alpha, beta and gamma and whose transformation points are at −13 °C and 795 °C. The beta form exists at room temperature and has a face-centered crystal structure while the high-temperature gamma form has a body-centered crystal structure.

Normally, the beta form has a metallic-like electrical conductivity, but becomes a semiconductor when exposed to around 16,000 atm (1.6 GPa). Its electrical resistivity is tenfold larger at about 39,000 atm (3.9 GPa) but then drops dramatically, to around 10% of its room temperature resistivity value, at 40,000 atm (4 GPa).

Ytterbium is one of the lanthanides that is able to become divalent. Like the other potentially divalent lanthanides, samarium and europium, it is capable of being extracted into mercury by the use of sodium amalgam, which made it one of the easier lanthanides to purify using classical techniques. However, this divalency was not discovered until the 20th century.

Technical Data
Symbol Yb Density (25 C)/gcm 6.973
Atomic number 70 Melting point / °C 824
No. of naturally occurring isotopes 7 Boiling point / °C -1427
Atomic weight 173.04(+/-3) ΔHfus/kJmol-1 3.35
Outer electron configuration 4f146s2 ΔHvap/kJmol-1 159
Metal radius(6-coordinate)/pm 193.3 ΔHf(monoatomic gas)/kJmol-1 152
Ionic radius(6-coordinate)/pm III 86.8 ΔH(hydration Ln3+)/kJmol-1 3739
Ionic radius(6-coordinate)/pm II 102 Electrical resistivity (25 C)/μohm cm  
Ionization energy/kJmol-1 I 603 E° (M3+(aq)\ + e- →M2+(aq))/V 28
Ionization energy/kJmol-1 II 1175 E° (M3+(aq)\ + 3e- →M(s))/V -3.472
Ionization energy/kJmol-1 III 2408  
Evaporation Techniques
Temperature (oC) @Vap. Pressure Techniques Remarks
10-8 Torr 10-6 Torr 10-4 Torr Electron Beam Crucible Coil Boat
520 Sublimes 590 Sublimes 690 Sublimes Good - - Tantalum  

Evaporation Materials
Y1-5000-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
Y1-3003-F 0.004" (0.1mm)
Y1-3007-F 0.008" (0.2mm)
Powder
Y1-10000-P -40 mesh
Rods
Y1-2000-R 0.250" (6.35mm)
Y1-2001-R 0.500" (12.7mm)
Sheet
Y1-4001-S 0.015" (0.38mm)
Y1-4002-S 0.020" (0.5mm)
Y1-4003-S 0.030" (0.76mm)
Y1-4004-S 0.040" (1mm)