Triphenylantimony(III)

See more Antimony products. Antimony (atomic symbol: Sb, atomic number: 51) is a Block P, Group 15, Period 5 element with an atomic radius of 121.760. The number of electrons in each of antimony's shells is 2, 8, 18, 18, 5 and its electron configuration is [Kr] 4d¹⁰ 5s² 5p³. The antimony atom has a radius of 140 pm and a Van der Waals radius of 206 pm. Antimony was discovered around 3000 BC and first isolated by Vannoccio Biringuccio in 1540 AD. In its elemental form, antimony has a silvery lustrous gray appearance. The most common source of antimony is the sulfide mineral known as stibnite (Sb₂S₃), although it sometimes occurs natively as well. Antimony has numerous applications, most commonly in flame-retardant materials. It also increases the hardness and strength of lead when combined in an alloy and is frequently employed as a dopant in semiconductor materials. Its name is derived from the Greek words anti and monos, meaning a metal not found by itself.