Beryllium Selenide

See more Beryllium products. Beryllium (atomic symbol: Be, atomic number: 4) is a Block S, Group 2, Period 2 element with an atomic weight of 9.012182. The number of electrons in each of Beryllium's shells is [2, 2] and its electron configuration is [He] 2s². The beryllium atom has a radius of 112 pm and a Van der Waals radius of 153 pm. Beryllium is a relatively rare element in the earth's crust; it can be found in minerals such as bertrandite, chrysoberyl, phenakite, and beryl, its most common source for commercial production. Beryllium was discovered by Louis Nicolas Vauquelin in 1797 and first isolated by Friedrich Wöhler and Antoine Bussy in 1828. In its elemental form, beryllium has a gray metallic appearance. It is a soft metal that is both strong and brittle; its low density and high thermal conductivity make it useful for aerospace and military applications. It is also frequently used in X-ray equipment and particle physics. The origin of the name Beryllium comes from the Greek word "beryllos," meaning beryl.

See more Selenium products. Selenium (atomic symbol: Se, atomic number: 34) is a Block P, Group 16, Period 4 element with an atomic radius of 78.96. The number of electrons in each of Selenium's shells is 2, 8, 18, 6 and its electron configuration is [Ar] 3d¹⁰ 4s² 4p⁴. The selenium atom has a radius of 120 pm and a Van der Waals radius of 190 pm. Selenium is a non-metal with several allotropes: a black, vitreous form with an irregular crystal structure three red-colored forms with monoclinic crystal structures and a gray form with a hexagonal crystal structure, the most stable and dense form of the element. One of the most common uses for selenium is in glass production the red tint that it lends to glass neutralizes green or yellow tints from impurities in the glass materials. Selenium was discovered and first isolated by Jöns Jakob Berzelius and Johann Gottlieb Gahn in 1817. The origin of the name Selenium comes from the Greek word "Selênê," meaning moon.