Gadolinium

Gadolinium (pronounced /ˌɡædɵˈlɪniəm/ GAD-o-LIN-ee-əm) is a chemical element that has the symbol Gd and atomic number 64. It is a silvery-white, malleable and ductile rare-earth metal. Gadolinium has exceptionally high absorption of neutrons and therefore is used for shielding in neutron radiography and in nuclear reactors. Because of its paramagnetic properties, solutions of organic gadolinium complexes and gadolinium compounds are the most popu... more

Gadolinium (pronounced /ˌɡædɵˈlɪniəm/ GAD-o-LIN-ee-əm) is a chemical element that has the symbol Gd and atomic number 64. It is a silvery-white, malleable and ductile rare-earth metal. Gadolinium has exceptionally high absorption of neutrons and therefore is used for shielding in neutron radiography and in nuclear reactors. Because of its paramagnetic properties, solutions of organic gadolinium complexes and gadolinium compounds are the most popular intravenous MRI contrast agents in medical magnetic resonance imaging. Gadolinium is a silvery-white malleable and ductile rare-earth metal. It crystallizes in hexagonal, close-packed α- form at room temperature, but, when heated to temperatures above 1235 °C, it transforms into its β- form, which has a body-centered cubic structure. Gadolinium-157 has the highest thermal neutron capture cross-section of any known nuclide except xenon-135, measured at 49,000 barns, but it also has a fast burn-out rate, limiting its usefulness as a nuclear... less