Thulium

  • thulium, 69tm
    thulium sublimed dendritic and 1cm3 cube.jpg
    thulium
    pronunciationm/ (thew-lee-əm)
    appearancesilvery gray
    standard atomic weight ar, std(tm)168.934218(6)[1]
    thulium in the periodic table
    hydrogen helium
    lithium beryllium boron carbon nitrogen oxygen fluorine neon
    sodium magnesium aluminium silicon phosphorus sulfur chlorine argon
    potassium calcium scandium titanium vanadium chromium manganese iron cobalt nickel copper zinc gallium germanium arsenic selenium bromine krypton
    rubidium strontium yttrium zirconium niobium molybdenum technetium ruthenium rhodium palladium silver cadmium indium tin antimony tellurium iodine xenon
    caesium barium lanthanum cerium praseodymium neodymium promethium samarium europium gadolinium terbium dysprosium holmium erbium thulium ytterbium lutetium hafnium tantalum tungsten rhenium osmium iridium platinum gold mercury (element) thallium lead bismuth polonium astatine radon
    francium radium actinium thorium protactinium uranium neptunium plutonium americium curium berkelium californium einsteinium fermium mendelevium nobelium lawrencium rutherfordium dubnium seaborgium bohrium hassium meitnerium darmstadtium roentgenium copernicium nihonium flerovium moscovium livermorium tennessine oganesson


    tm

    md
    erbiumthuliumytterbium
    atomic number (z)69
    groupgroup n/a
    periodperiod 6
    blockf-block
    element category  lanthanide
    electron configuration[xe] 4f13 6s2
    electrons per shell2, 8, 18, 31, 8, 2
    physical properties
    phase at stpsolid
    melting point1818 k ​(1545 °c, ​2813 °f)
    boiling point2223 k ​(1950 °c, ​3542 °f)
    density (near r.t.)9.32 g/cm3
    when liquid (at m.p.)8.56 g/cm3
    heat of fusion16.84 kj/mol
    heat of vaporization191 kj/mol
    molar heat capacity27.03 j/(mol·k)
    vapor pressure
    p (pa) 1 10 100 1 k 10 k 100 k
    at t (k) 1117 1235 1381 1570 (1821) (2217)
    atomic properties
    oxidation states+2, +3 (a basic oxide)
    electronegativitypauling scale: 1.25
    ionization energies
    • 1st: 596.7 kj/mol
    • 2nd: 1160 kj/mol
    • 3rd: 2285 kj/mol
    atomic radiusempirical: 176 pm
    covalent radius190±10 pm
    color lines in a spectral range
    spectral lines of thulium
    other properties
    natural occurrenceprimordial
    crystal structurehexagonal close-packed (hcp)
    hexagonal close packed crystal structure for thulium
    thermal expansionpoly: 13.3 µm/(m·k) (at r.t.)
    thermal conductivity16.9 w/(m·k)
    electrical resistivitypoly: 676 nΩ·m (at r.t.)
    magnetic orderingparamagnetic (at 300 k)
    magnetic susceptibility+25,500·10−6 cm3/mol (291 k)[2]
    young's modulus74.0 gpa
    shear modulus30.5 gpa
    bulk modulus44.5 gpa
    poisson ratio0.213
    vickers hardness470–650 mpa
    brinell hardness470–900 mpa
    cas number7440-30-4
    history
    namingafter thule, a mythical region in scandinavia
    discovery and first isolationper teodor cleve (1879)
    main isotopes of thulium
    iso­tope abun­dance half-life (t1/2) decay mode pro­duct
    167tm syn 9.25 d ε 167er
    168tm syn 93.1 d ε 168er
    169tm 100% stable
    170tm syn 128.6 d β 170yb
    171tm syn 1.92 y β 171yb
    category category: thulium
    | references

    thulium is a chemical element with the symbol tm and atomic number 69. it is the thirteenth and third-last element in the lanthanide series. like the other lanthanides, the most common oxidation state is +3, seen in its oxide, halides and other compounds; because it occurs so late in the series, however, the +2 oxidation state is also stabilized by the nearly full 4f shell that results. in aqueous solution, like compounds of other late lanthanides, soluble thulium compounds form coordination complexes with nine water molecules.

    in 1879, the swedish chemist per teodor cleve separated from the rare earth oxide erbia another two previously unknown components, which he called holmia and thulia; these were the oxides of holmium and thulium, respectively. a relatively pure sample of thulium metal was first obtained in 1911.

    thulium is the second-least abundant of the lanthanides, after radioactively unstable promethium which is only found in trace quantities on earth. it is an easily workable metal with a bright silvery-gray luster. it is fairly soft and slowly tarnishes in air. despite its high price and rarity, thulium is used as the radiation source in portable x-ray devices, and in some solid-state lasers. it has no significant biological role and is not particularly toxic.

  • properties
  • history
  • occurrence
  • production
  • applications
  • biological role and precautions
  • see also
  • references
  • external links

Thulium, 69Tm
Thulium sublimed dendritic and 1cm3 cube.jpg
Thulium
Pronunciationm/ (THEW-lee-əm)
Appearancesilvery gray
Standard atomic weight Ar, std(Tm)168.934218(6)[1]
Thulium in the periodic table
Hydrogen Helium
Lithium Beryllium Boron Carbon Nitrogen Oxygen Fluorine Neon
Sodium Magnesium Aluminium Silicon Phosphorus Sulfur Chlorine Argon
Potassium Calcium Scandium Titanium Vanadium Chromium Manganese Iron Cobalt Nickel Copper Zinc Gallium Germanium Arsenic Selenium Bromine Krypton
Rubidium Strontium Yttrium Zirconium Niobium Molybdenum Technetium Ruthenium Rhodium Palladium Silver Cadmium Indium Tin Antimony Tellurium Iodine Xenon
Caesium Barium Lanthanum Cerium Praseodymium Neodymium Promethium Samarium Europium Gadolinium Terbium Dysprosium Holmium Erbium Thulium Ytterbium Lutetium Hafnium Tantalum Tungsten Rhenium Osmium Iridium Platinum Gold Mercury (element) Thallium Lead Bismuth Polonium Astatine Radon
Francium Radium Actinium Thorium Protactinium Uranium Neptunium Plutonium Americium Curium Berkelium Californium Einsteinium Fermium Mendelevium Nobelium Lawrencium Rutherfordium Dubnium Seaborgium Bohrium Hassium Meitnerium Darmstadtium Roentgenium Copernicium Nihonium Flerovium Moscovium Livermorium Tennessine Oganesson


Tm

Md
erbiumthuliumytterbium
Atomic number (Z)69
Groupgroup n/a
Periodperiod 6
Blockf-block
Element category  Lanthanide
Electron configuration[Xe] 4f13 6s2
Electrons per shell2, 8, 18, 31, 8, 2
Physical properties
Phase at STPsolid
Melting point1818 K ​(1545 °C, ​2813 °F)
Boiling point2223 K ​(1950 °C, ​3542 °F)
Density (near r.t.)9.32 g/cm3
when liquid (at m.p.)8.56 g/cm3
Heat of fusion16.84 kJ/mol
Heat of vaporization191 kJ/mol
Molar heat capacity27.03 J/(mol·K)
Vapor pressure
P (Pa) 1 10 100 1 k 10 k 100 k
at T (K) 1117 1235 1381 1570 (1821) (2217)
Atomic properties
Oxidation states+2, +3 (a basic oxide)
ElectronegativityPauling scale: 1.25
Ionization energies
  • 1st: 596.7 kJ/mol
  • 2nd: 1160 kJ/mol
  • 3rd: 2285 kJ/mol
Atomic radiusempirical: 176 pm
Covalent radius190±10 pm
Color lines in a spectral range
Spectral lines of thulium
Other properties
Natural occurrenceprimordial
Crystal structurehexagonal close-packed (hcp)
Hexagonal close packed crystal structure for thulium
Thermal expansionpoly: 13.3 µm/(m·K) (at r.t.)
Thermal conductivity16.9 W/(m·K)
Electrical resistivitypoly: 676 nΩ·m (at r.t.)
Magnetic orderingparamagnetic (at 300 K)
Magnetic susceptibility+25,500·10−6 cm3/mol (291 K)[2]
Young's modulus74.0 GPa
Shear modulus30.5 GPa
Bulk modulus44.5 GPa
Poisson ratio0.213
Vickers hardness470–650 MPa
Brinell hardness470–900 MPa
CAS Number7440-30-4
History
Namingafter Thule, a mythical region in Scandinavia
Discovery and first isolationPer Teodor Cleve (1879)
Main isotopes of thulium
Iso­tope Abun­dance Half-life (t1/2) Decay mode Pro­duct
167Tm syn 9.25 d ε 167Er
168Tm syn 93.1 d ε 168Er
169Tm 100% stable
170Tm syn 128.6 d β 170Yb
171Tm syn 1.92 y β 171Yb
Category Category: Thulium
| references

Thulium is a chemical element with the symbol Tm and atomic number 69. It is the thirteenth and third-last element in the lanthanide series. Like the other lanthanides, the most common oxidation state is +3, seen in its oxide, halides and other compounds; because it occurs so late in the series, however, the +2 oxidation state is also stabilized by the nearly full 4f shell that results. In aqueous solution, like compounds of other late lanthanides, soluble thulium compounds form coordination complexes with nine water molecules.

In 1879, the Swedish chemist Per Teodor Cleve separated from the rare earth oxide erbia another two previously unknown components, which he called holmia and thulia; these were the oxides of holmium and thulium, respectively. A relatively pure sample of thulium metal was first obtained in 1911.

Thulium is the second-least abundant of the lanthanides, after radioactively unstable promethium which is only found in trace quantities on Earth. It is an easily workable metal with a bright silvery-gray luster. It is fairly soft and slowly tarnishes in air. Despite its high price and rarity, thulium is used as the radiation source in portable X-ray devices, and in some solid-state lasers. It has no significant biological role and is not particularly toxic.