Gadolinium is a chemical element that has the symbol Gd and atomic number 64.
Gadolinium is a silvery-white, malleable and ductile rare-earth metal with a metallic luster. It crystallizes in hexagonal, close-packed alpha form at room temperature, but, when heated to 1508 K or more, it transforms into its beta form, which has a body-centered cubic structure.
Unlike other rare earth elements, gadolinium is relatively stable in dry air. However, it tarnishes quickly in moist air and forms a loosely-adhering oxide that spalls off, and then exposes more surface to oxidation. Gadolinium reacts slowly with water, and it is soluble in dilute acids.
Gadolinium-157 has the highest thermal neutron capture cross-section of any known nuclide with the exception of Xenon-135, 49,000 barns, but it also has a fast burn-out rate, limiting its usefulness as a nuclear control rod material.
Gadolinium becomes superconductive below a critical temperature of 1.083 K. It is strongly paramagnetic at room temperature, and exhibits ferromagnetic properties below room temperature.
Gadolinium demonstrates a magnetocaloric effect whereby its temperature increases when it enters a magnetic field and decreases when it leaves the magnetic field. The effect is considerably stronger for the gadolinium alloy Gd5(Si2Ge2).
Symbol | Gd | Density (20°C)/gcm-3 | 7.886 |
Atomic number | 64 | Melting point /°C | 1312 |
No. of naturally occurring isotopes | 7 | Boiling point /°C | -3000 |
Atomic weight | 157.25 (+/-3) | ΔHvap/kJmol-1 | 301 |
Outer electron configuration | 4f7d46s2 | ΔHf(monoatomic gas/kJmol-1 | 398 |
Metal radius(6-coordinate)/pm | 180.4 | ΔH(hydration Ln3+)/kJmol-1 | 3571 |
Ionic radius(6-coordinate)/pm III | 93.8 | Ionization energy/kJ mol-1 I | 595 |
Ionic radius(6-coordinate)/pm II | - | Ionization energy/kJmol-1 II | 1172 |
Electrical resistivity | Ionization energy/kJmol-1 III | 1999 | |
(25°C)/μohm cm | 134 |
Temperature (oC) @Vap. Pressure | Techniques | Remarks | |||||
10-8 Torr | 10-6 Torr | 10-4 Torr | Electron Beam | Crucible | Coil | Boat | |
760 | 900 | 1175 | Excellent | Al2O3 | - | Tantalum | High Tantalum solubility. |
G1-5000-M 1-4mm pieces |
G1-5001-M Ingot (Please ask for sizes) |
G1-5002-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.
G1-3003-F 0.004" (0.1mm) |
G1-3007-F 0.008" (0.2mm) |
G1-10000-P -40 mesh |
G1-2000-R 0.250" (6.35mm) |
G1-2001-R 0.500" (12.7mm) |
G1-4002-S 0.020" (0.5mm) |
G1-4003-S 0.030" (0.76mm) |
G1-4004-S 0.040" (1.0mm) |