Thulium Elemental Symbol

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Thulium Thulium Tulio Túlio Tulio Tulium

Elemental Thulium PictureThulium is a Block F, Group 3, Period 6 element. Thulium Bohr ModelThe number of electrons in each of Thulium's shells is 2, 8, 18, 31, 8, 2 and its electronic configuration is [Xe]4f136s2. In its elemental form, CAS 7440-30-4, thulium has a silvery-white appearance. The thulium atom has a radius of and it's Van der Waals radius is unknown. Thulium is representative of the other lanthanides (rare earths) similar in chemistry to Yttrium. Thulium, first discovered by Theodore Cleve in 1879, is found in small quantities in minerals such as monazite. Thulium is named after "Thule", which is the ancient name of Scandinavia.

Thulium emits blue upon excitation. Flat panel screens depend critically on bright blue emitters. Also, under X-ray bombardment emissions are in both the 375 nm (ultra violet) and 465 (visible blue) wave lengths. This gives the material useful applications in low radiation detection for detection badges and similar uses. It is also used in other luminescence applications, such as halide discharge lamps. Flat panel screens depend critically on bright blue emitters. High Purity (99.999%) Thulium Oxide (Tm2O3) Powder Thulium is available as metal and compounds with purities from 99% to 99.999% (ACS grade to ultra-high purity). Elemental or metallic forms include pellets, rod, wire and granules for evaporation source material purposes. High Purity (99.999%) Thulium (Tm) Sputtering Target Thulium nanoparticles and nanopowders provide ultra-high surface area which nanotechnology research and recent experiments demonstrate function to create new and unique properties and benefits. Oxides are available in powder and dense pellet form for such uses as optical coating and thin film applications. Oxides tend to be insoluble. Fluorides are another insoluble form for uses in which oxygen is undesirable such as metallurgy, chemical and physical vapor deposition and in some optical coatings. Thulium is also available in soluble forms including chlorides, nitrates and acetates. These compounds can be manufactured as solutions at specified stoichiometries.

Thulium is not toxic in its elemental form, however. safety data for Thulium and its compounds can vary widely depending on the form. For potential hazard information, toxicity, and road, sea and air transportation limitations, such as DOT Hazard Class, DOT Number, EU Number, NFPA Health rating and RTECS Class, please see the specific material or compound referenced in the Products tab below.

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Thulium Properties

Symbol: Tm Melting Point: 1545 oC, 2813 oF, 1818.15 K
Atomic Number: 69 Boiling Point: 1950 oC, 3542 oF, 2223.15 K
Atomic Weight: 168.93 Density: 9321 kg/m³
Element Category: Lanthanides Liquid Density @ Melting Point: 8.56 g·cm−3
Group, Period, Block: n/a, 6, f Specific Heat: 0.0382 Cal/g/K @ 25 °C
    Heat of Vaporization 59 K-Cal/gm atom at 1947°C
CHEMICAL STRUCTURE Heat of Fusion 4.40 Cal/gm mole
Electrons: 69 Thermal Conductivity: 0.169 W/cm/K @ 298.2 K
Protons: 69 Thermal Expansion: (r.t.) (poly) 13.3 µm/(m·K)
Neutrons: 100 Electrical Resistivity: 79.0 microhm-cm @ 25°C
Electron Configuration: [Xe] 4f136s2 Electronegativity: 1.2 Paulings
Atomic Radius: 176 pm Tensile Strength: 60 MPa
Covalent Radius: 190±10 pm Molar Heat Capacity: 27.03 J·mol−1·K−1
Van der Waals radius: 227 pm Young's Modulus: 74.0 GPa
Oxidation States: 2, 3, 4 (basic oxide) Shear Modulus: 30.5 GPa
Phase: Solid Bulk Modulus: 44.5 GPa
Crystal Structure: hexagonal close-packed Poisson Ratio: 0.213
Magnetic Ordering: paramagnetic Mohs Hardness: N/A
1st Ionization Energy: 59.70 kJ mol-1 Vickers Hardness: 520 MPa
2nd Ionization Energy: 1162.66 kJ mol-1 Brinell Hardness: 471 MPa
3rd Ionization Energy: 2284.79 kJ mol-1 Speed of Sound: N/A
CAS Number: 7440-30-4 Abundance in typical human body, by weight: N/A
ChemSpider ID: 22400 Abundance in typical human body, by atom: N/A
PubChem CID: 23961 Abundance in universe, by weight: 0.1 ppb
MDL Number: MFCD00011281 Abundance in universe, by atom: 0.001 ppb
EC Number: 231-140-2 Discovered By: Per Teodor Cleve
Beilstein Number: N/A Discovery Date: 1879
SMILES Identifier: [Tm]  
InChI Identifier: InChI=1S/Tm Other Names: Tulio

Thulium Products

Metal Forms  •  Compounds  •  Oxide Forms  •  Organometallic Compounds
Sputtering Targets  •  Nanomaterials  •  Semiconductor Materials

Recent Research & Development for Thulium

  • CMarisa J. Monreal, Robert K. Thomson, Brian L. Scott, Jaqueline L. Kiplinger, Enhancing the synthetic efficacy of thorium tetrachloride bis(1,2-dimethoxyethane) with added 1,2-dimethoxyethane: Preparation of metallocene thorium dichlorides, Inorganic Chemistry Communications, Volume 46, August 2014
  • Deepak Rawat, Smruti Dash, A.R. Joshi, Thermodynamic studies of thorium phosphate diphosphate and phase investigations of Th-P-O and Th-P-H2O systems, Thermochimica Acta, Volume 581, 10 April 2014
  • M.G. Brik, First-principles studies of the structural, electronic, and optical properties of a novel thorium compound Rb2Th7Se15, Journal of Solid State Chemistry, Volume 212, April 2014
  • Moshiel Biton, Assaf Shamir, Michael Shandalov, Neta Arad-Vosk, Amir Sa'ar, Eyal Yahel, Yuval Golan, Chemical deposition and characterization of thorium-alloyed lead sulfide thin films, Thin Solid Films, Volume 556, 1 April 2014
  • Clément Falaise, Christophe Volkringer, Thierry Loiseau, Isolation of thorium benzoate polytypes with discrete ThO8 square antiprismatic units involved in chain-like assemblies, Inorganic Chemistry Communications, Volume 39, January 2014
  • Yingjie Zhang, Mohan Bhadbhade, Jiabin Gao, Inna Karatchevtseva, Jason R. Price, Gregory R. Lumpkin, Synthesis and crystal structures of uranium (VI) and thorium (IV) complexes with picolinamide and malonamide, Inorganic Chemistry Communications, Volume 37, November 2013
  • A.N. Turanov, V.K. Karandashev, V.M. Masalov, A.A. Zhokhov, G.A. Emelchenko, Adsorption of lanthanides(III), uranium(VI) and thorium(IV) from nitric acid solutions by carbon inverse opals modified with tetraphenylmethylenediphospine dioxide, Journal of Colloid and Interface Science, Volume 405, 1 September 2013
  • K.O. Obodo, N. Chetty, A theoretical study of thorium titanium-based alloys, Journal of Nuclear Materials, Volume 440, Issues 1–3, September 2013
  • Meera Keskar, S.K. Sali, N.D. Dahale, K. Krishnan, N.K. Kulkarni, R. Phatak, S. Kannan, Thermal stability and expansion studies of cesium molybdates and cesium thorium molybdates, Journal of Nuclear Materials, Volume 438, Issues 1–3, July 2013
  • D. Pérez Daroca, S. Jaroszewicz, A.M. Llois, H.O. Mosca, Phonon spectrum, mechanical and thermophysical properties of thorium carbide, Journal of Nuclear Materials, Volume 437, Issues 1–3, June 2013

Thulium Isotopes

Naturally occurring thulium (Tm) has 1 stable isotope, 169Tm.

Nuclide Symbol Isotopic Mass Half-Life Nuclear Spin
169Tm 168.9342133 Observationally Stable 1/2 +