A NIR phosphorescent osmium(ii) complex as a lysosome tracking reagent and photodynamic therapeutic agent.

See more Osmium products. Osmium (atomic symbol: Os, atomic number: 76) is a Block D, Group 8, Period 6 element with an atomic weight of 190.23. The number of electrons in each of osmium's shells is [2, 8, 18, 32, 14, 2] and its electron configuration is [Xe] 4f¹⁴ 5d⁶ 6s². The osmium atom has a radius of 135 pm and a Van der Waals radius of 216 pm. Osmium was discovered and first isolated by Smithson Tennant in 1803. In its elemental form, osmium has a silvery blue cast apperance. Osmium has the highest melting point and the lowest vapor pressure of any of the platinum group of metals it is also the densest naturally ocurring element. Osmium is the least abundant stable element in the earth's crust. It is found in the alloys osmiridium and iridiosmium and as a free element. The origin of the name Osmium comes from the Greek word osme, meaning a smell or odor.