Thulium Antimonide

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.

See more Thulium products. Thulium (atomic symbol: Tm, atomic number: 69) is a Block F, Group 3, Period 6 element with an atomic weight of 168.93421. The number of electrons in each of Thulium's shells is [2, 8, 18, 31, 8, 2] and its electron configuration is [Xe]4f¹³6s². The thulium atom has a radius of 176 pm and a Van der Waals radius of 227 pm. In its elemental form, thulium has a silvery-gray appearance. Thulium is representative of the other lanthanides (rare earths) and similar in chemistry to yttrium. It is the least abundant of the rare earth elements. Thulium emits blue upon excitation, and is used in flat panel screens that depend critically on bright blue emitters. Thulium was discovered and first isolated by Per Teodor Cleve in 1879. It is named after "Thule," which is the ancient name of Scandinavia.