Lutetium Arsenate

See more Arsenic products. Arsenic (atomic symbol: As, atomic number: 33) is a Block P, Group 15, Period 4 element with an atomic radius of 74.92160. The number of electrons in each of arsenic's shells is 2, 8, 18, 5 and its electron configuration is [Ar] 3d¹⁰ 4s² 4p³. The arsenic atom has a radius of 119 pm and a Van der Waals radius of 185 pm. Arsenic was discovered in the early Bronze Age, circa 2500 BC. It was first isolated by Albertus Magnus in 1250 AD. In its elemental form, arsenic is a metallic grey, brittle, crystalline, semimetallic solid. Arsenic is found in numerous minerals including arsenolite (As₂O₃), arsenopyrite (FeAsS), loellingite (FeAs₂), orpiment (As₂S₃), and realgar (As₄S₄). Arsenic has numerous applications as a semiconductor and other electronic applications as indium arsenide, silicon arsenide and tin arsenide. Arsenic is finding increasing uses as a doping agent in solid-state devices such as transistors.

See more Lutetium products. Lutetium (atomic symbol: Lu, atomic number: 71) is a Block F, Group 3, Period 6 element with an atomic weight of 174.9668. The number of electrons in each of Lutetium's shells is [2, 8, 18, 32, 9, 2] and its electron configuration is [Xe] 4f¹⁵ 5d¹ 6s². In its elemental form, lutetium has a silvery-white appearance. The lutetium atom has a radius of 174 pm and a Van der Waals radius of 221 pm. Lutetium was discovered and first isolated by Georges Urbain, Carl Auer von Welsbach and Charles James in 1906, all independently of each other. Urbain was awarded the naming honor because he published his findings first. Lutetium is the last member of the rare earth series. Unlike most rare earths it lacks a magnetic moment. It has the smallest metallic radius of any rare earth and it is perhaps the least naturally abundant of the lanthanides. The most common source of commercially produced lutetium is the mineral monazite. The name lutetium originates from the Latin word Lutetia, meaning Paris. Lutetium is found with almost all other rare earth metals, but it never occurs naturally by itself.