Holmium Elemental Symbol

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Holmium Holmium Olmio Hólmio Holmio Holmium

Elemental Holmium PictureHolmium is a Block F, Group 3, Period 6 element. Holmium Bohr ModelThe number of electrons in each of Holmium's shells is 2, 8, 18, 29, 8, 2 and its electronic configuration is [Xe] 4f11 6s2. In its elemental form, CAS 7440-60-0, holmium has a silvery white appearance.. The holmium atom has a radius of 174.3.pm and it's Van der Waals radius is unknown. Holmium was first discovered by J.L. Soret in 1878.

Holmium has the highest magnetic moment (10.6µB) of any naturally occurring element. Because of this it has been used to create the highest known magnetic fields by placing it within high strength magnets as a pole piece or magnetic flux concentrator. This magnetic property also has value in yttrium-iron-garnet (YIG) lasers for microwave equipment. Holmium lases at a human eye safe 2.08 microns allowing its use in a variety of medical and dental applications in both yttrium-aluminum-garnet (YAG) and yttrium-lanthanum-fluoride (YLF) solid state lasers. The wavelength allows for use in silica fibers designed for shorter wavelengths while still providing the cutting strength of longer wave length equipment. Holmium is available as metal and compounds with purities from 99% to 99.999% (ACS grade to ultra-high purity). High Purity (99.999%) Holmium Oxide (Ho2O3) Powder Elemental or metallic forms include pellets, rod, wire and granules for evaporation source material purposes. High Purity (99.999%) Holmium (Ho) Sputtering TargetHolmium 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. Holmium is also available in soluble forms including chlorides, nitrates and acetates. These compounds can be manufactured as solutions at specified stoichiometries.

Holmium is slightly toxic in its elemental form. Safety data for Holmium 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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Holmium Properties

Symbol: Ho Melting Point: 1472 oC, 2681.6 oF, 1745.15 K
Atomic Number: 67 Boiling Point: 2700 oC, 4892 oF, 2973.15 K
Atomic Weight: 164.93 Density: 8.795 gm/cc
Element Category: Lanthanides Liquid Density @ Melting Point: 8.34 g·cm−3
Group, Period, Block: n/a, 6, f Specific Heat: 0.0393 Cal/g/ K @ 25 °C
    Heat of Vaporization 67 K-Cal/gm atom at 2695°C
CHEMICAL STRUCTURE Heat of Fusion 4.10 Cal/gm mole
Electrons: 67 Thermal Conductivity: 0.162 W/cm/ K @ 298.2 K
Protons: 67 Thermal Expansion: (r.t.) (poly) 11.2 µm/(m·K)
Neutrons: 98 Electrical Resistivity: 87.0 microhm-cm @ 25°C
Electron Configuration: [Xe] 4f116s2 Electronegativity: 1.2 Paulings
Atomic Radius: 176 pm Tensile Strength: N/A
Covalent Radius: 192±7 pm Molar Heat Capacity: 27.15 J·mol−1·K−1
Van der Waals radius: 216 pm Young's Modulus: 64.8 GPa
Oxidation States: 3, 2, 1 (basic oxide) Shear Modulus: 26.3 GPa
Phase: Solid Bulk Modulus: 40.2 GPa
Crystal Structure: hexagonal close-packed Poisson Ratio: 0.231
Magnetic Ordering: paramagnetic Mohs Hardness: N/A
1st Ionization Energy: 580.99 kJ mol-1 Vickers Hardness: 481 MPa
2nd Ionization Energy: 1138.54 kJ mol-1 Brinell Hardness: 746 MPa
3rd Ionization Energy: 2203.74 kJ mol-1 Speed of Sound: (20 °C) 2760 m·s−1
CAS Number: 7440-60-0 Abundance in typical human body, by weight: N/A
ChemSpider ID: 22424 Abundance in typical human body, by atom: N/A
PubChem CID: 23988 Abundance in universe, by weight: 0.5 ppb
MDL Number: MFCD00011049 Abundance in universe, by atom: 0.004 ppb
EC Number: 231-169-0 Discovered By: Marc Delafontaine
Beilstein Number: N/A Discovery Date: 1878
SMILES Identifier: [Ho]  
InChI Identifier: InChI=1S/Ho Other Names: Olmio, Hólmio

Holmium Products

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

Recent Research & Development for Holmium

  • In-Vitro Evaluation of LithAssist: A Novel Combined Holmium Laser and Suction Device. Okhunov Z, Del Junco M, Yoon R, Labadie K, Lusch A, Ordon M. J Endourol. 2014.
  • Optimizing Use of the Holmium:YAG Laser for Surgical Management of Urinary Lithiasis. Patel AP, Knudsen BE. Curr Urol Rep. 2014
  • Holmium-yttrium aluminum garnet laser lithotripsy in the treatment of biliary calculi using single-operator cholangioscopy: a multicenter experience (with video). Patel SN, Rosenkranz L, Hooks B, Tarnasky PR, Raijman I, Fishman DS, Sauer BG, Kahaleh M. Gastrointest Endosc. 2014 Feb.
  • Holmium(III)-selective fluorimetric optode based on N,N-bis(salicylidene)-naphthylene-1,8-diamine as a neutral fluorogenic ionophore. Ganjali MR, Hosseini M, Karimi A, Haji-Hashemi H, Salavati-Niasari M, Norouzi P. Spectrochim Acta A Mol Biomol Spectrosc. 2014 Mar.
  • Safety and feasibility of concomitant surgery during holmium laser enucleation of the prostate (HoLEP). Patel A, Nunez R, Mmeje CO, Humphreys MR. World J Urol. 2014 Feb.
  • Holmium laser enucleation of the prostate versus transurethral resection of the prostate: a randomized clinical trial. Sun N, Fu Y, Tian T, Gao J, Wang Y, Wang S, An W. Int Urol Nephrol. 2014 Feb. 
  • A Novel Paraboloid Intracorporeal Lithotripter: Computer Aided Design Analysis and In Vitro Comparison with Holmium Laser for Large Renal Calculi. Rawandale-Patil A, Mulay A, Patni LG, Patil P. J Endourol. 2014 Jan.
  • Holmium-yttrium aluminum garnet laser lithotripsy in the treatment of biliary calculi using single-operator cholangioscopy: a multicenter experience (with video). Gastrointest Endosc. 2013 create date:2013/11/26 | first author:Patel SN
  • Sialoendoscopy with and without holmium:YAG laser-assisted lithotripsy in the management of obstructive sialadenitis of major salivary glands. Sionis S, Caria RA, Trucas M, Brennan PA, Puxeddu R. Br J Oral Maxillofac Surg. 2014 Jan
  • Holmium:YAG Transurethral Incision Versus Laser Photoselective Vaporization for Benign Prostatic Hyperplasia in a Small Prostate. Elshal AM, Elkoushy MA, Elmansy HM, Sampalis J, Elhilali MM. Urol. 2014 Jan.
  • Effect of Holmium Laser Enucleation of Prostate on Overactive Bladder Symptoms and Urodynamic Parameters: A Prospective Study. Kwon O, Lee HE, Bae J, Oh JK, Oh SJ. Urology. 2013 Dec.
  • Thermal properties of holmium-implanted gold films for a neutrino mass experiment with cryogenic microcalorimeters. Prasai K, Alves E, Bagliani D, Yanardag SB, Biasotti M, Galeazzi M, Gatti F, Gomes MR, Rocha J, Uprety Y. Rev Sci Instrum. 2013.
  • Holmium Laser Enucleation of the Prostate Is Safe in Patients with Prostate Cancer and Lower Urinary Tract Symptoms-A Retrospective Feasibility Study. Becker A, Placke A, Kluth L, Schwarz R, Isbarn H, Chun F, Heuer R, Schlomm T, Seiler D, Engel O, Fisch M, Graefen M, Ahyai SA. J Endourol. 2013 Dec.
  • Percutaneous transhepatic endoscopic holmium laser lithotripsy for intrahepatic and choledochal biliary stones. Ierardi AM, Fontana F, Petrillo M, Floridi C, Cocozza E, Segato S, Abbas HA, Mangano A, Carrafiello G, Dionigi R. Int J Surg.
  • Use of holmium:YAG laser in posterior urethral valves: Another method of fulguration. J Pediatr Urol. 2013 | first author:Mandal S
  • Sialoendoscopy with and without holmium:YAG laser-assisted lithotripsy in the management of obstructive sialadenitis of major salivary glands. Br J Oral Maxillofac Surg. 2013 | first author:Sionis S
  • A novel paraboloid intracorporeal lithotripter: CAD analysis and invitro comparison with Holmium laser for large renal calculi. J Endourol. 2013 | first author:Rawandale-Patil AV
  • Stabilizing the magnetic moment of single holmium atoms by symmetry. Nature. 2013 | first author:Miyamachi T
  • Flexible cystoscopy and Holmium:Yttrium aluminum garnet laser ablation for recurrent nonmuscle invasive bladder carcinoma under local anesthesia. Syed HA, Talbot N, Abbas A, MacDonald D, Jones R, Marr TJ, Rukin NJ. J Endourol.

Holmium Isotopes

Holmium has one stable isotope: 165Ho.

Nuclide Symbol Isotopic Mass Half-Life Nuclear Spin
165Ho 164.9303221 Observationally Stable 7/2-