Actinium Elemental Symbol

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Actinium Actinium Attinio Actínio Actinio Aktinium

Actinium Bohr ModelActinium is an F-Block, Period 7 element. The number of electrons in each of Actinium's shells is 2,8,18,32,18,9,2 and its electron configuration is [Rn] 6d1 7s2. Actinium The actinium atom has a radius of 195 pm. In its elemental form, CAS 7440-34-8, actinium has a silvery-white appearance. Actinium is a radioactive metal that rapidly reacts with the combination of moisture in the air and oxygen to form a white coating of actinium oxide which prevents further oxidation. Actinium is found naturally in uranium ores. It rarely occurs as a free element in the earth’s crust. It can be made in the lab, but it has very minimal important uses. Actinium was first noted as a new element by a French chemist, André-Louis Debierne, in 1899. It was discovered again as an independent element in 1902 by German chemist Friedrich Oskar Giesel.

Actinium information, including Technical Data, Safety Data and its high purity properties, research, applications and other useful facts are discussed below. Scientific facts such as the atomic structure, ionization energy, abundance on Earth, conductivity and thermal properties are included.

  • Properties
  • Research
  • Isotopes
  • Other Elements

Actinium Properties

Symbol: Ac Melting Point: 1050 oC, 1922 oF, 1323.15 K
Atomic Number: 89 Boiling Point: 3200 oC, 5792 oF, 3473.15 K
Atomic Weight: 227 Density: 10060  kg m-3
Element Category: Actinide Liquid Density @ Melting Point: N/A
Group, Period, Block: n/a, 7, f Specific Heat: N/A
    Heat of Vaporization 400 kJ·mol−1
CHEMICAL STRUCTURE Heat of Fusion 14 kJ·mol−1
Electrons: 89 Thermal Conductivity: 12 W·m−1·K−1
Protons: 89 Thermal Expansion: N/A
Neutrons: 139 Electrical Resistivity: N/A
Electron Configuration: [Rn] 6d17s2 Electronegativity: 1.1 (Pauling scale)
Atomic Radius: 215 pm Tensile Strength: N/A
Covalent Radius: N/A Molar Heat Capacity: N/A
Van der Waals radius: N/A Young's Modulus: N/A
Oxidation States: 3 (neutral oxide) Shear Modulus: N/A
Phase: Solid Bulk Modulus: N/A
Crystal Structure: Cubic Poisson Ratio: N/A
Magnetic Ordering: N/A Mohs Hardness: N/A
1st Ionization Energy: 499 kJ·mol−1 Vickers Hardness: N/A
2nd Ionization Energy: 1170 kJ·mol−1 Brinell Hardness: N/A
3rd Ionization Energy: N/A Speed of Sound: N/A
CAS Number: 7440-34-8 Abundance in typical human body, by weight: N/A
ChemSpider ID: 22404 Abundance in typical human body, by atom: N/A
PubChem CID: 23965 Abundance in universe, by weight: N/A
MDL Number: N/A Abundance in universe, by atom: N/A
EC Number: N/A Discovered By: André-Louis Debierne
Beilstein Number: N/A Discovery Date: 1899
SMILES Identifier: [Ac]  
InChI Identifier: InChI=1S/Ac Other Names: Attinio

Recent Research & Development for Actinium

  • Production of high-purity radium-223 from legacy actinium-beryllium neutron sources. Soderquist CZ, McNamara BK, Fisher DR. Curr Radiopharm. 2012 Jul;5(3):244-52.
  • Bismuth-213 and actinium-225 -- generator performance and evolving therapeutic applications of two generator-derived alpha-emitting radioisotopes. Morgenstern A, Bruchertseifer F, Apostolidis C. Curr Radiopharm. 2012 Jul;5(3):221-7. Review.
  • Actinium-225 in targeted alpha-particle therapeutic applications. Scheinberg DA, McDevitt MR. Curr Radiopharm. 2011 Oct;4(4):306-20. Review.
  • LaPO4 nanoparticles doped with actinium-225 that partially sequester daughter radionuclides. Woodward J, Kennel SJ, Stuckey A, Osborne D, Wall J, Rondinone AJ, Standaert RF, Mirzadeh S. Bioconjug Chem. 2011 Apr 20;22(4):766-76. doi: 10.1021/bc100574f. Epub 2011 Mar 24.
  • Renal uptake of bismuth-213 and its contribution to kidney radiation dose following administration of actinium-225-labeled antibody. Schwartz J, Jaggi JS, O'Donoghue JA, Ruan S, McDevitt M, Larson SM, Scheinberg DA, Humm JL. Phys Med Biol. 2011 Feb 7;56(3):721-33. doi: 10.1088/0031-9155/56/3/012. Epub 2011 Jan 10.
  • Radium-228 analysis of natural waters by Cherenkov counting of Actinium-228. Aleissa KA, Almasoud FI, Islam MS, L'Annunziata MF. Appl Radiat Isot. 2008 Dec;66(12):1954-63. doi: 10.1016/j.apradiso.2008.05.012. Epub 2008 Jun 10.
  • Realizing the potential of the Actinium-225 radionuclide generator in targeted alpha particle therapy applications. Miederer M, Scheinberg DA, McDevitt MR. Adv Drug Deliv Rev. 2008 Sep;60(12):1371-82. doi: 10.1016/j.addr.2008.04.009. Epub 2008 Apr 23. Review.
  • Enhanced retention of the alpha-particle-emitting daughters of Actinium-225 by liposome carriers. Sofou S, Kappel BJ, Jaggi JS, McDevitt MR, Scheinberg DA, Sgouros G. Bioconjug Chem. 2007 Nov-Dec;18(6):2061-7. Epub 2007 Oct 13.
  • Influence of the linker on the biodistribution and catabolism of actinium-225 self-immolative tumor-targeted isotope generators. Antczak C, Jaggi JS, LeFave CV, Curcio MJ, McDevitt MR, Scheinberg DA. Bioconjug Chem. 2006 Nov-Dec;17(6):1551-60.
  • Vertical distribution, migration rates, and model comparison of actinium in a semi-arid environment. McClellan Y, August RA, Gosz JR, Gann S, Parmenter RR, Windsor M. J Environ Radioact. 2006;86(2):199-211. Epub 2005 Oct 21.
  • Renal tubulointerstitial changes after internal irradiation with alpha-particle-emitting actinium daughters. Jaggi JS, Seshan SV, McDevitt MR, LaPerle K, Sgouros G, Scheinberg DA. J Am Soc Nephrol. 2005 Sep;16(9):2677-89. Epub 2005 Jun 29.
  • Production of actinium-225 for alpha particle mediated radioimmunotherapy. Boll RA, Malkemus D, Mirzadeh S. Appl Radiat Isot. 2005 May;62(5):667-79. Epub 2005 Jan 28.
  • Alpha-particle emitting atomic generator (Actinium-225)-labeled trastuzumab (herceptin) targeting of breast cancer spheroids: efficacy versus HER2/neu expression. Ballangrud AM, Yang WH, Palm S, Enmon R, Borchardt PE, Pellegrini VA, McDevitt MR, Scheinberg DA, Sgouros G. Clin Cancer Res. 2004 Jul 1;10(13):4489-97.
  • Sterically stabilized liposomes as a carrier for alpha-emitting radium and actinium radionuclides. Henriksen G, Schoultz BW, Michaelsen TE, Bruland ØS, Larsen RH. Nucl Med Biol. 2004 May;31(4):441-9.
  • Thorium and actinium polyphosphonate compounds as bone-seeking alpha particle-emitting agents. Henriksen G, Bruland OS, Larsen RH. Anticancer Res. 2004 Jan-Feb;24(1):101-5.
  • Targeted actinium-225 in vivo generators for therapy of ovarian cancer. Borchardt PE, Yuan RR, Miederer M, McDevitt MR, Scheinberg DA. Cancer Res. 2003 Aug 15;63(16):5084-90.
  • Actinium-225 conjugates of MAb CC49 and humanized delta CH2CC49. Kennel SJ, Brechbiel MW, Milenic DE, Schlom J, Mirzadeh S. Cancer Biother Radiopharm. 2002 Apr;17(2):219-31.
  • Improved in vivo stability of actinium-225 macrocyclic complexes. Deal KA, Davis IA, Mirzadeh S, Kennel SJ, Brechbiel MW. J Med Chem. 1999 Jul 29;42(15):2988-92.
  • Sequential determination of radium-226, radium-228, actinium-227, and thorium isotopes in environmental and process waste samples. Percival DR, Martin DB. Anal Chem. 1974 Oct;46(12):1742-9. No abstract available.
  • [Radiation safety in work with substances containing actinium]. Andreeva OS, Malinina VI. Gig Sanit. 1971 May;36(5):43-7. Russian. No abstract available.

Actinium Isotopes

Actinium has no stable isotopes.