Secondary Amides as Hydrogen Atom Transfer Promoters for Reactions of Samarium Diiodide.

See more Samarium products. Samarium (atomic symbol: Sm, atomic number: 62) is a Block F, Group 3, Period 6 element with an atomic radius of 150.36. The number of electrons in each of samarium's shells is 2, 8, 18, 24, 8, 2 and its electron configuration is [Xe]4f⁶ 6s². The samarium atom has a radius of 180 pm and a Van der Waals radius of 229 pm. In its elemental form, samarium has a silvery-white appearance. Samarium is not found as free element in nature. It is found in the minerals cerite, gadolinite, samarskite, monazite and bastnäsite. Samarium is classified as a rare earth element and is the 40th most abundant element in the Earth's crust. Samarium was discovered and first isolated by Lecoq de Boisbaudran in 1879. It is named after the mineral samarskite, the mineral from which it was isolated.

See more Iodine products. Iodine (atomic symbol: I, atomic number: 53) is a Block P, Group 17, Period 5 element with an atomic radius of 126.90447. The number of electrons in each of Iodine's shells is 2, 8, 18, 18, 7 and its electron configuration is [Kr] 4d¹⁰ 5s² 5p⁵. The iodine atom has a radius of 140 pm and a Van der Waals radius of 198 pm. In its elemental form, iodine has a lustrous metallic gray appearance as a solid and a violet appearance as a gas or liquid solution. Iodine forms compounds with many elements, but is less active than the other halogens. It dissolves readily in chloroform, carbon tetrachloride, or carbon disulfide. Iodine compounds are important in organic chemistry and very useful in the field of medicine. Iodine was discovered and first isolated by Bernard Courtois in 1811. The name Iodine is derived from the Greek word "iodes" meaning violet.