Dysprosium Facts - Element 66 or Dy

Dysprosium is a silver rare earth metal with atomic number 66 and element symbol Dy. Like other rare earth elements, it has many applications in modern society. Here are interesting dysprosium facts, including its history, uses, sources, and properties.

Dysprosium Facts

• Paul Lecoq de Boisbaudran identified dysprosium in 1886, but it wasn't isolated as a pure metal until the 1950s by Frank Spedding. Boisbaudran named the element dysprosium from the Greek word dysprositos, which means "hard to get". This reflects the difficulty Boisbaudran had separating the element from its oxide (it took over 30 attempts, still yielding an impure product).
• At room temperature, dysprosium is a bright silver metal that slowly oxidizes in air and readily burns. It is soft enough to be cut with a knife. The metal tolerates machining so long as it isn't overheated (which can lead to sparking and ignition).
• While most of the properties of element 66 are comparable to those of other rare earth, it has unusually high magnetic strength (as does holmium). Dy is ferromagnetic at temperatures below 85K (−188.2 °C). Above this temperature, it transitions to a helical antiferromagnetic state, yielding to ​a disordered paramagnetic state at 179 K (−94 °C).
• Dysprosium, like related elements, does not occur free in nature. It is found in several minerals, including xenotime and monazite sand. The element is obtained as a by-product of yttrium extraction using a magnet or flotation process followed by ion exchange displacement to obtain either dysprosium fluoride or dysprosium chloride. Finally, the pure metal is obtained by reacting the halide with calcium or lithium metal.
• The abundance of dysprosium is 5.2 mg/kg in the Earth's crust and 0.9 ng/L in sea water.
• Natural element 66 consists of a mixture of seven stable isotopes. The most abundant is Dy-154 (28%). Twenty-nine radioisotopes have been synthesized, plus there are at least 11 metastable isomers.
• Dysprosium is used in nuclear control rods for its high thermal neutron cross-section, in data storage for its high magnetic susceptibility, in magnetostrictive materials, and in rare earth magnets. It is combined with other elements as a source of infrared radiation, in dosimeters, and to make high strength nanofibers. The trivalent dysprosium ion displays interesting luminescence, leading to its use in lasers, diodes, metal halide lamps, and phosphorescent materials.
• Dysprosium serves no known biological function. Soluble dysprosium compounds are mildly toxic if ingested or inhaled, while insoluble compounds are considered non-toxic. The pure metal presents a hazard because it reacts with water to form flammable hydrogen and reacts with air to ignite. Powdered Dy and thin Dy foil can explode in the presence of a spark. The fire cannot be extinguished using water. Certain dysprosium compounds, including its nitrate, will ignite upon contact with human skin and other organic materials.

Dysprosium Properties

Element Name: dysprosium

Element Symbol: Dy

Atomic Number: 66

Atomic Weight: 162.500(1)

Discovery: Lecoq de Boisbaudran (1886)

Element Group: f-block, rare earth, lanthanide

Element Period: period 6

Electron Shell Configuration: [Xe] 4f¹⁰ 6s² (2, 8, 18, 28, 8, 2)

Phase: solid

Density: 8.540 g/cm³ (near room temperature)

Melting Point: 1680 K  (1407 °C, 2565 °F)

Boiling Point: 2840 K (2562 °C, 4653 °F)

Oxidation States: 4, 3, 2, 1

Heat of Fusion: 11.06 kJ/mol

Heat of Vaporization: 280 kJ/mol

Molar Heat Capacity: 27.7 J/(mol·K)

Electronegativity: Pauling scale: 1.22

Ionization Energy: 1st: 573.0 kJ/mol, 2nd: 1130 kJ/mol, 3rd: 2200 kJ/mol

Atomic Radius: 178 picometers

Crystal Structure: hexagonal close-packed (hcp)

Magnetic Ordering: paramagnetic (at 300K)